MLZ User Meeting 2025

3 Dec 2025, 11:30 → 4 Dec 2025, 16:00 Europe/Berlin

smartvillage Bogenhausen

 

A new approach

After holding more than ten User Meetings, we would like to try something new and change our format! As it will be the last User Meeting before the planned restart of the FRM II in 2026, the main focus will be on this topic. In addition to the Directors’ update and the talk by this year’s MLZ awardee, the preparations of the instrument teams and service groups will be presented in a dedicated plenary session before posters will introduce the new features of the instruments. We look forward to all your questions and hope to stimulate many discussions! 

Due to this different approach, there will be a limited number of parallel talks and poster spaces. However, we look forward to receiving your abstracts and giving you the opportunity to present your research using neutrons and positrons. 

We are happy to host the confirmed plenary talks by Hanna Barriga (KTH Stockholm, Sweden) on nanomedicine and Jasper Landman (Uni Wageningen, The Netherlands) on food science. 

For your travel plans: As usual, we will start at around noon with lunch. There will be a dinner in a Bavarian restaurant on the evening of the 03rd, and the event will end in the afternoon on the 04th. 

Please note: The QENS-workshop by our DEVA Group on Dec 02^nd is fully booked now!

Maps Dinner: Karlsplatz underground station.pdf Venue: Arabellapark bus and underground station.pdf

Wednesday 3 December

11:30 🍴Light lunch

12:25 Onboarding by smartvillage team

Welcome: Update by MLZ Directors and MLZ Award Ceremony

1 Update by the MLZ Directors and MLZ User Committee

Speakers: Christian Pfleiderer (TUM FRM II), Prof. Martin Müller (Helmholtz-Zentrum hereon GmbH), Tommy Nylander (Lund University)

2 Welcome address by KFN

Speaker: Michael Schulz

3 MLZ Award 2025: Laudatio and Awardee Talk

14:30 ☕️Coffee

Neutrons & Users 1a: Materials Engineering

Conveners: Michael Hofmann, Ralph Gilles

4 From Inhomogeneity to Insight: Neutron Imaging in Modern Materials Science

Inhomogeneity is a defining feature of real-world materials - whether in composition, phase, strain, or defect distribution - and plays a central role in determining their mechanical and functional behavior. Neutron imaging, with its unique ability to penetrate dense structural materials, has evolved into a powerful, non-destructive tool for visualizing such internal complexity across macroscopic volumes.

Recent advances in instrumentation and methodologies have extended its capabilities far beyond conventional attenuation contrast, enabling the exploitation of imaging modalities previously accessible only through neutron scattering techniques. Notably, diffraction contrast allows for spatially resolved characterization of texture, strain, and crystallographic phase distributions, while inelastic scattering contrast facilitates the probing of temperature fields during in-situ processing.

In some cases, these contrast mechanisms can be complemented by Digital Volume Correlation (DVC) applied to X-ray or neutron computed tomography data, allowing the quantification of internal deformation fields under load.

Together, these emerging techniques make it possible to visualize not only bulk structures, but also to resolve heterogeneities, including cracks and pores, track localized deformation, and even detect the early onset of plasticity — bridging the gap between microstructural behavior and macroscopic performance. This multimodal approach holds particular promise for advancing the understanding of hydrogen embrittlement in metallic alloys, a long-standing challenge in structural materials research.

Speaker: Robin Woracek (European Spallation Source ERIC)

5 Bridging Scales: From Lattice Strains to Industrial Sheet Metal Forming of Dual-Phase Steels

Dual-phase steels are widely used in industrial sheet forming due to their high strength–ductility balance, but their complex microstructural response under load poses challenges for accurate process simulation. In this work, we present in-situ measurements, where lattice strains from synchrotron diffraction were combined with global strain data to capture the elasto-plastic behavior of a dual-phase steel under uniaxial loading. These experimental insights provide the basis for the calibration of a representative volume element (RVE) within a crystal plasticity finite element method (CPFEM) framework. The calibrated RVE allows us to link microstructural mechanisms to macroscopic response, and thereby to assess the transferability of the identified material parameters into large-scale sheet metal forming simulations. Our study demonstrates how synchrotron-based experiments can support the calibration of physically informed CPFEM models that improve the predictive capability of industrial forming process simulations.

Speaker: Lorenz Maier (utg)

6 Elucidating the photochromic properties of yttrium oxyhydride films using positron annihilation spectroscopy

Yttrium oxyhydride (YHxOy) is a promising mixed-anion semiconductor in view of its photochromic properties, offering prospects for applications in smart windows. The origin of its pronounced color-neutral photodarkening upon UV illumination and the subsequent process of bleaching back to the transparent state is topic of our investigations. We present in-situ illumination studies based on Positron Annihilation Lifetime Spectroscopy (PALS) and Doppler Broadening Positron Annihilation Spectroscopy (DB-PAS).

In-situ illumination DB-PAS shows that the Doppler S parameter increases progressively upon subsequent photodarkening-bleaching cycling, indicating the formation of open volume defects. Detailed insights are gained from PALS in combination with DFT calculations, demonstrating that yttrium vacancies are present in the as-deposited films, while yttrium-hydrogen divacancies are formed during illumination, pointing to the liberation of hydrogen from octahedral sites in the lattice. Upon cycling, a clear correlation between the evolution of the S parameter and the bleaching kinetics is observed, suggesting that the formation of hydrogen vacancies and/or hydrogen loss is key to understanding the slowing down of the bleaching process. Simultaneously, partially reversible shifts in the Doppler S-W parameters during photodarkening-bleaching are observed. These support the Anderson-Mott insulator-metal transition model for the photochromism, in which electrons localize at hydrogen vacancies and lead to a local metallic electronic structure at sufficiently high concentrations, transforming about 4-8 vol% of the films. During bleaching, in-situ illumination PALS reveals a strong correlation between the lifetime of the first positron annihilation component and the optical transmittance, providing further insights into the evolution of the metallic regions during bleaching.

Speaker: Dr Stephan Eijt (Delft University of Technology)

Neutrons & Users 1b: From Polymers to Proteins

Conveners: Henrich Frielinghaus (JCNS), Michaela Zamponi (Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum)

7 What high pressure can teach us about block copolymer micelles with a thermoresponsive shell

In dilute aqueous solution, diblock copolymers with a hydrophobic and a thermo-responsive block self-assemble into core-shell micelles. Here, we present the self-assembly behavior of the diblock copolymer PMMA-b-PNIPAM consisting of a short hydrophobic poly(methyl methacrylate) and a long thermoresponsive poly(N-isopropylacrylamide) block. Synchrotron small-angle X-ray scattering reveals that, below the cloud point CP, spherical micelles are formed, having a PMMA core and a hydrated PNIPAM shell. Above the CP, the micellar shell dehydrates and contracts, and the micelles form aggregates [1]. Applying pressure to an aqueous micellar solution of PMMA-b-PNIPAM is a tool to alter the hydration behavior of the PNIPAM block [2]. We find that not only the value of the CP, but also the transition behavior depends on pressure [3]. The pressure-induced alteration of the properties of the micellar shell and the correlation between the micelles allows investigating the relation between these effects.

References
[1] Ko, C.-H., Papadakis, C. M. et al. Self-Assembled Micelles from Thermoresponsive Poly(methyl methacrylate)-b-poly(N-isopropylacrylamide) Diblock Copolymers in Aqueous Solution. Macromolecules 2021, 54, 384.
[2] Papadakis, C. M.; Niebuur, B.-J.; Schulte, A. Thermoresponsive Polymers under Pressure with a Focus on Poly(N-isopropylacrylamide) (PNIPAM). Langmuir 2024, 40, 1.
[3] Alvarez Herrera, P. A., Papadakis, C. M. et al. Effect of Pressure on the Micellar Structure of PMMA b PNIPAM Diblock Copolymers in Aqueous Solution. Macromolecules 2024, 57, 10263.

Speaker: Prof. Christine M. Papadakis (Technical University of Munich, TUM School of Natural Sciences, Soft Matter Physics Group)

8 Insights into structural properties of the complex coacervates and dynamics in the complex model lipid membrane

Single chain nano particles (SCNPs) are model system to decipher intrinsically disordered proteins. Here, we have probed the effect of salt/polymer concentration, cross link density, and charge density. Poly-l-lysine-SCNPs (PLL-SCNPs) prepared by tuning intramolecular crosslinking, solvent condition and ionic strength. Structural result show that radius of gyration of PLL-SCNP lowers by varying the crosslinker and salt concentration compared to linear PLL (PLL). PLL, PLL-SCNP with RNA, PLL/RNA and PLL-SCNP/RNA respectively, and acetylated PLL (ac-PLL/RNA) form polyelectrolyte complex (PEC) coacervate. The correlation length reduces for PLL-SCNP/RNA suggest variation in the internal topology. Topology probed independent of charge density was ensured by reacting ac with PLL which show similar correlation length as PLL-SCNP/RNA. Furthermore, we have studied the effect of nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin (Asp), diclofenac (Diclo) and ibuprofen (Ibu) on the dynamics of brain lipids (BLs) unilamellar vesicles (BLs-ULVs), physiologically relevant membrane, using quasi elastic neutron scattering (QENS) and neutron spin echo (NSE). It is found that Asp, Diclo and Ibu fasten whole lipid diffusion at highest, lowest and intermediate concentration, respectively. NSE result show that, Asp stiffens, Diclo softens BLs membrane and Ibu does not affect bending rigidity (κKBT). This study enhances our understanding of the biomimetic systems and its biomedical implications.

Speaker: Dr Purushottam Dubey (Centro de Fizika Materiales (CSIS/UPV-EHU))

9 What Neutrons and X-rays Tell Us About Plant-based Food Emulsions?

The market for plant-based food alternatives is growing. One group of these plant-based alternatives are emulsions. Plant-based emulsions have been in the scientific focus for a decade focusing on their stability, or their interfacial stabilization processes. One representative of plant-based emulsifiers are green biomass proteins like RuBisCo. Research questions about details in interfacial stabilization processes of green biomass proteins remain unanswered so far.
Small angle neutron and X-ray scattering as well as neutron spin echo spectroscopy deliver valuable insides on protein structure and emulsion stabilization mechanisms [1,2]. Utilizing these techniques will help to uncover details of the interfacial structure and dynamics [3,4].
In this study, acid precipitated, microfiltrated and ultrafiltrated green biomass proteins derived from alfalfa (Medicago sativa L.) are currently investigated with SAXS, SANS and NSE on their ability to stabilize emulsions. Results indicate that the green biomass proteins with Ribulose-1,5-Bisphospat Carboxylase/Oxygenase as its main component can stabilize emulsions. The shape of the proteins did not significantly change upon adsorption to the interface. The dynamics reveal an agile movement of the proteins at the oil/water interface.
This is the first step to understand green biomass protein stabilized emulsions in a more detailed way. The results will guide to a knowledge driven improvement of plant-based emulsion systems.
[1] T. Heiden-Hecht et al., New insights into protein stabilized emulsions captured via neutron and X-ray scattering: An approach with β-lactoglobulin at triacylglyceride-oil/water interfaces, J Colloid Interface Sci 655 (2024) 319–326. https://doi.org/10.1016/j.jcis.2023.10.155.
[2] M. Corredig, et al., Boosting structural food science using X-ray and neutron techniques, Food Hydrocoll 170 (2026). https://doi.org/10.1016/j.foodhyd.2025.111674.
[3] Maren Müller, et al., Proteins derived from green biomass: Emulsions stabilized by alfalfa (Medicago sativa L.) and water lentil (Lemna minor L.) concentrate at acidic pH, In Preparation (2025).
[4] M. Müller, et al., Proteins derived from green biomass: Alfalfa (Medicago sativa L.) and water lentil concentrate (Lemna minor L.) in the focus as stabilizers for emulsions, Food Hydrocolloids for Health 8 (2025). https://doi.org/10.1016/j.fhfh.2025.100233.

Speaker: Maren Müller

Neutrons & Users 1c: Structural Chemistry

Conveners: Anatoliy Senyshyn, Dr Martin Meven (RWTH Aachen University, Institute of Crystallography - Outstation at MLZ)

10 In situ neutron diffraction as a guide for chemical synthesis

Time-resolved in situ investigations are very useful for unveiling basic steps of chemical reactions. They are of fundamental importance for many technologically relevant processes, e. g. hydrogen storage, electrochemical energy storage or ore smelting, and allow for elucidation of reaction pathways and the identification of intermediates thus enabling better reaction control [1-4]. Neutron diffraction is particularly useful when it comes to light elements such as hydrogen or lithium and has advantages for bulky sample environment due to low absorption cross sections for most elements. Considerations for the design of sample environment allowing for in situ neutron diffraction on chemical reactions in the solid as a function of time, gas pressure and flow, temperature, and other external parameters will be discussed [5]. Examples will be given from the areas of research of intermetallic hydrides as hydrogen storage materials [1-3], heteroanionic hydrides as functional materials [6] and ore smelting [7]. A detailed knowledge of the formation conditions has oftentimes proven to be the key to a rational synthesis planning. The chemical synthesis of solids can thus be considerably improved by in situ neutron diffraction investigations. Further, it strengthens our fundamental understanding of chemical reactions in the solid state.

[1] T. C. Hansen, H. Kohlmann, Chemical Reactions followed by in situ Neutron Powder Diffraction, Z. Anorg. Allg. Chem. 2014, 640, 3044–3063.
[2] V. K. Peterson, J. E. Auckett, W.-K. Pang, Real-time powder diffraction studies of energy materials under non-equilibrium conditions, IUCrJ 2017, 4, 540–554.
[3] H. Kohlmann, Looking into the Black Box of Solid-State Synthesis, Eur. J. Inorg. Chem. 2019, 4174–4180; doi: doi.org/10.1002/ejic.201900733.
[4] R. Finger, N. Kurtzemann, T. C. Hansen, H. Kohlmann, Design and use of a sapphire single-crystal gas-pressure cell for in situ neutron powder diffraction, J. Appl. Crystallogr. 2021, 54, 839–846; doi.org/10.1107/S1600576721002685.
[5] N. Zapp, F. Oehler, M. Bertmer, H. Auer, D. Sheptyakov, C. Ritter, H. Kohlmann, Aliovalent anion substitution as a design concept for heteroanionic Ruddlesden–Popper hydrides, Chem. Commun. 2022, 58, 12971–12974; doi.org/10.1039/D2CC04356D.
[6] M. Häger, S. Keilholz, H. Kohlmann, The reduction of group 6–8 transition metal oxides with hydrogen — from ore smelting to reaction pathways, Eur. J. Inorg. Chem. 2025, accepted.

Speaker: Prof. Holger Kohlmann (Universität Leipzig)

11 Temperature-dependent Crystal Structure of Dimethyl Carbonate

The performance and safety/stability of Li-ion batteries (LIBs) can be enhanced by optimizing the charge-storing electrode materials and/or the charge transfer-mediating liquid electrolytes. In LIB research, the major focus has been on the electrode subsystem, while liquid electrolytes are studied much less [1].
Upon cooling of LIBs to investigate their performance at low temperatures, a series of Bragg reflections has been observed, which was assigned to the freezing of the liquid electrolyte [2]. Additional measurements reveal the development of long-range order in the model electrolyte mixture LP30 (ethylene carbonate (EC), dimethyl carbonate (DMC), and 1 M LiPF6). To further study this evolving order, the individual components of the system must be examined. Of particular interest are insights close to ambient conditions, for such in situ LIB studies at sub-ambient temperatures.
This contribution outlines our efforts to crystallize DMC with minimized preferred orientation, in order to study the unit cell across the entire solid temperature range using neutron- and synchrotron-based powder diffraction techniques. Additionally, the datasets are complemented by x-ray single-crystal diffraction measurements.
[1] B. Flamme et al., Green Chem. 19, 1828-1849 (2017). (https://doi.org/10.1039/C7GC00252A)
[2] A. Senyshyn et al., Journal of Power Sources 282, 235-240 (2015). (http://doi.org/10.1016/j.jpowsour.2015.02.008)

Speaker: Lea Westphal (TUM/MLZ)

12 Quantum refinement for neutron macromolecular crystallography

Neutron crystallography is a powerful method to determine the positions of hydrogen atoms in macromolecular structures. However, it is sometimes hard to judge what would constitute a chemically reasonable model, and the geometry of H atoms depends more on the surroundings (for example the formation of hydrogen bonds) than heavy atoms, so that the empirical geometry information for the hydrogen atoms used to supplement the experimental data is often less accurate. These problems may be reduced by using quantum-mechanical calculations, allowing to extract the maximal amount of information from the neutron data. We have recently implemented quantum refinement interfacing the widely used structure-refinement software Phenix and the freely available quantum mechanical software ORCA. This opens for quantum-mechanically supported structure determination with all structure methods available in Phenix, including neutron crystallography and overcomes some of the limitations in our previous implementation.

Speaker: Esko Oksanen (Lund University & European Spallation Source ESS ERIC)

16:00 ☕️Coffee

Neutrons & Users 2a: Hydrogen.metal interactions

Conveners: Dr Sebastian Busch (GEMS at MLZ, Helmholtz-Zentrum Hereon, Germany), Sebastian Muehlbauer

13 Hydrogen Effects in Superalloys - Insights from Neutron and X-Ray diffraction

Alloy 718, a widely used Ni-based superalloy, is susceptible to hydrogen embrittlement. The γ' and γ'' precipitates and the δ phase significantly contribute to this embrittlement. To determine if other superalloys with different grain boundary pinning phases exhibit similar behavior, we investigated two γ' strengthened CoNiCr-based superalloys containing B2-structured β or D85-structured µ phase particles. NanoSIMS mapping revealed the highest hydrogen concentration localized in the grain boundary pinning µ and β precipitates, confirmed by synchrotron diffraction showing significant lattice expansion post hydrogen charging. Neutron diffraction indicates that the γ' phase absorbs more hydrogen than the γ phase, leading to greater expansion and increased lattice misfit between γ and γ' phases. Atom probe tomography results confirm preferred hydrogen partitioning towards the γ' phase. Tensile tests reveal that hydrogen markedly affects the mechanical properties of samples charged with high-pressure hydrogen. The hydrogen accumulation in intermetallic particles and strengthening precipitates promotes crack initiation and facilitates propagation along weakened γ/γ' interfaces. These findings enhance our understanding of hydrogen embrittlement in superalloys and aid in developing more hydrogen-resistant alloys.

Speaker: Steffen Neumeier (Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg)

14 Probing Hydrogen Ingress in Ti–Mg Hybrid Implant Materials via Neutron and Synchrotron Tomography and Diffraction

Hybrid implants that combine a permanent Ti-based component with a degradable Mg-part offer a promising strategy for advanced biomedical applications. This design combines the high strength and long-term stability of titanium with the temporary structural support, bone growth stimulation, and potential drug delivery functions of magnesium. During degradation, Mg releases hydrogen gas, which can diffuse into the Ti matrix and alter its properties. The distribution of hydrogen within Ti is therefore a key factor in determining the long-term mechanical stability of such implants.
To investigate this at the microscopic scale, Ti6Al4V–Mg0.6Zn0.5Ca hybrid samples produced by metal injection molding were subjected to saline degradation for up to 120 hours. Hydrogen ingress was analyzed using neutron tomography, synchrotron X-ray tomography and diffraction, SEM, and the gas fusion method. Results revealed a radially uniform hydrogen distribution, while the axial profile correlated well with macroscopic measurements.

Speaker: Cecilia Solis

15 Hydrogen distribution in single-crystal superalloys and its dependence on the y/y' lattice misfit

The importance of hydrogen embrittlement (HE) will increase with the energy transition, as hydrogen (H) is a promising fuel for CO₂-free power generation. In aviation, the replacement of kerosene by H requires turbine materials resistant to HE. Single-crystal (SX) superalloys are the material of choice for the hottest turbine sections, where the lattice parameter misfit between y and y' is a critical design parameter. As y' precipitates are coherently embedded in the matrix, the sign and magnitude of the y/y' misfit determine local elastic stresses that may influence H partitioning. In this study, three SX superalloys were investigated: CMSX-4 (slightly negative misfit, ~-0.1 %), LDSX6A (large negative misfit, ~-0.8 %), and VF60 (positive misfit, ~+0.5 %). Samples were H-charged under high pressure (900 bar, 300 °C) and studied ex situ by neutron diffraction (ENGIN-X at ISIS) and laboratory XRD. Results show that H consistently accumulates in the y' phase, independent of misfit. Thermal desorption spectroscopy also indicates that H solubility is governed primarily by chemical composition. Compression tests reveal earlier fracture and reduced work-hardening rates in hydrogen-charged samples, which is further characterized with SEM/TEM of interrupted tests.
These findings provide important insights into the influence of y/y' lattice misfit on hydrogen uptake and its consequences for mechanical properties.

Speaker: Oliver Nagel (Friedrich-Alexander-Universität Erlangen-Nürnberg)

Neutrons & Users 2b: Particle Physics with UCNs

Conveners: Bastian Märkisch (Physik-Department, TUM), Peter Fierlinger (TUM)

16 The Quantum Bouncing Ball & Gravity Resonance Spectroscopy

We present a resonant spectroscopy technique devoted to the study of gravitation and the related cosmological problems of Dark Matter and Dark Energy. The object is a quantum mechanical wavepacket of an ultra-cold neutron, and the new method extends the techniques of Purcel, Rabi and Ramsey to neutron quantum states in the gravity potential of the Earth. The technique is named Gravity Resonance Spectroscopy (GRS) in close analogy to Magnetic Resonance Spectroscopy (MRS). Here a neutron in the gravity potential of the Earth is placed on a reflecting mirror, and transitions between the gravitational quantum states are performed by applying mechanical oscillations of the mirror with the proper transition frequency, whereas in MRS technique, an atom, a molecule or a nucleus with a magnetic moment is placed in an outer magnetic field and transitions between the magnetic Zeeman splitting are performed by applying proper oscillations of radiofrequency fields. Resonant transitions between several of the lowest quantum states are observed for the first time.

The strength of GRS is that it does not rely on electromagnetic interactions. The use of neutrons as test particles bypasses the electromagnetic background induced by van der Waals forces and other polarizability effects providing the key to a sensitivity of several orders of magnitude below the sensitivity of atoms.

Speaker: Hartmut Abele (Vienna University of Technology)

17 Electric Dipole Moments

As one of the most important probes for physics beyond the standard model of particle physics, the field of Electric Dipole Moment (EDM) searches is very active in theory and experiments. An overview of the broader landscape will be given, and the still essential role of the neutron as a clean and comparably simple probe will be discussed, together with experimental perspectives with more strong ultracold-neutron sources being functional.

Speaker: Peter Fierlinger (TUM)

18 The Neutron Lifetime - A Puzzle Revisited

The decay of the free neutron offers many opportunities to determine fundamental parameters in the Standard Model of particle physics, and also plays an important role in cosmology. The lifetime of the neutron is of particular importance, especially since it should be easy to measure in principle.

Even though we discovered the neutron almost a hundred years ago, experimental physicists face an embarrassing dilemma; the result of the measurements seems to depend on the measurement method. More precise measurements in the past 30 years have revealed an increasing, unexplained tension of nearly 10 seconds between the two main neutron lifetime experiment types!

For more than two decades, we have been developing a new instrument at TUM: PENeLOPE combines both measurement methods and should also make it possible to reduce the statistically and systematically limited measurement uncertainties by an order of magnitude. A key installation is a powerful source of ultra-cold neutrons, such as the one currently under construction at FRMII. However, in order to obtain initial measurements more quickly, the instrument, whose basic components have been completed, was relocated to TRIUMF, Vancouver, where it was set up and subjected to initial tests this year. This presentation will reveal details of both the physical motivation and the measurement method, as well as the current status of PENeLOPE.

Speaker: Jacqueline Dellith (FRM II)

Neutrons & Users 2c: Quantum Phenomena

Conveners: Johanna Jochum, Dr Yixi Su (JCNS-MLZ)

19 Low temperature lattice dynamics of KTaO3

Many emergent properties of great interest occur near a quantum critical point were a second-order transition is suppressed to zero temperature. Hence, a significant focus of current condensed matter is the study of susceptibilities and order parameters in materials that are influenced by quantum fluctuations. Structural phase transitions close to zero temperature provide ideal platforms for such studies, and the ferroelectric transition, in which cations and anions within a unit cell coherently displace to generate a net, switchable electric dipole moment, is particularly valuable since ferroelectrics have clearly defined susceptibilities (electric permittivity) and order parameters (net dipole moment) that can be investigated in conjunction with the structural phase transition. In this vein, quantum paraelectrics are of significant interest because they are thought to have ferroelectric order suppressed by quantum fluctuations. KTaO3 is considered a prototypical paraelectric, lying very close to a quantum critical point such that slight compositional substitutions induce ferroelectricity or even superconductivity to emerge as ground-states.

We applied cold neutron triple-axis and thermal neutron time-of-flight spectroscopy techniques combined with x-ray diffraction and DFPT calculations to provide a complete picture of the lattice dynamics in KTaO3 and answer the question concerning its alleged quantum paraelectric low-temperature properties.

Speaker: Yuliia Tymoshenko (TU Dresden)

20 Revealing nanoscale magnetic correlations in thin films with near-surface SANS

The discovery of topological protected states in chiral magnets inspired a renaissance in the field of non-collinear magnetism, and led to the identification of several long-wavelength spin objects including skyrmions, merons, solitons, and chiral bobbers. Small angle neutron scattering (SANS) has provided fundamental insights of these magnetic textures in bulk materials, whose associated topological properties are discussed in the context of low-energy information carriers. SANS of such structures in thin films or micro-structured bulk materials is, however, strongly limited by the tiny scattering volume and the prohibitively large background scattering by the substrate and support structures.

In this talk I will discuss near-surface SANS, performed slightly above the critical angle of reflection, as a route to overcome the shortcomings of transmission SANS for extremely small magnetic sample volumes in the thin-film limit [1]. Proof-of-concept measurements performed on bulk MnSi establish equivalent scattering patterns of the helical, conical, and skyrmion lattice phases between transmission and near-surface SANS geometries [2]. Near-surface SANS performed on epitaxial MnSi reveals a phase diagram which differs distinctly from bulk, and comprises of a single-domain, out-of-plane propagating helix with λ = 11.5 nm in zero-field. Our experimental findings are supported by micromagnetic simulations which depict a magnetic phase diagram dominated by a field-induced unwinding of soliton layers. Field and temperature history provide specific routes for the nucleation of the distinct soliton phases, comprising namely of four-, three-, two-, and single-soliton layers depending on the field strength. This work showcases the applicability of NS-SANS for the study of nano-confined magnetic materials, which would otherwise possess insufficient scattering volumes to be measured in transmission, and provides insights into the role of anisotropy and dimensionality on the phase diagrams of micro-structured bulk materials.

[1] G. L. Causer, J. Appl. Cryst., 58, 1455-1461 (2025)
[2] G. L. Causer et al., J. Appl. Cryst., 56, 26-35 (2023)

Speaker: Grace Causer

21 Non-equilibrium phases in skyrmion lattices

In cubic chiral magnets, the efficient coupling of magnetic skyrmion lattices to spin currents and magnetic fields permits their dynamical manipulation. When placed in a magnetic field with a slowly oscillating direction, the skyrmion lattice can be depinned, realizing a non-equilibrium state with vanishing depinning currents. With the combination of oscillating magnetic fields and applied electric currents, we explore a rich non-equilibrium phase diagram characterized by distinct stages of skyrmion lattice unpinning. We propose an effective slip–stick model for the bending and motion of the skyrmion lines in the presence of disorder, which reproduces key features observed in transverse susceptibility and time-resolved small-angle neutron scattering measurements and describes the existence of several dynamical skyrmion lattice phases under shaking and pushing, representing new phases of matter far from thermal equilibrium.

Speaker: Denis Mettus (Technische Universität München)

19:00 🍽️Dinner

Thursday 4 December

Highlights & Restart: Scientific Plenary Talks

Conveners: Alexandros Koutsioumpas (JCNS), Olaf Holderer (Forschungszentrum Jülich GmbH, JCNS at MLZ)

22 Studying structure – function relationships in lipid nanocarriers for the delivery of oligonucleotides

Lipid nanoparticles (LNPs) are the delivery technology in the mRNA SARS-CoV-2 vaccines, and they are now being screened to deliver a broad variety of biological drugs. Despite their success, rational design of lipid based nanocarriers for precision medicine applications is complex. One of the key barriers is our current limited ability to relate nanoparticle structure and chemical composition to cellular uptake and payload delivery.
We have used small angle scattering (X rays and neutrons) to study structure and function relationships in lipid nanocarriers. Our studies demonstrated that the structure of our nanoparticles impacts their interactions in biological environments including enzyme (phospholipase) activity(1) and delivery of oligonucleotides.(2)

Using this approach, we have designed a panel of LNPs focusing on distinct lipid organizations with minimal compositional variation. Our results demonstrate that the inverted hexagonal phase (HII) morphology is not a necessary condition for delivery using these LNPs. This highlights the importance of advanced characterisation for rational design of LNPs to enable the study of structure – function relationships.

References
(1) H.M.G. Barriga, I.J. Pence, M.N. Holme, J.J. Doutch, J. Penders, V. Nele, M.R. Thomas, M. Carroni, M.M. Stevens, Advanced Materials 2022, 34 (26)
(2) M. Ojansivu, H.M.G. Barriga, M.N. Holme, S. Morf, J.J. Doutch, T. Kjellman, M. Johnsson, J. Barauskas, M.M. Stevens, Advanced Materials 2025, 37 (17)

Speaker: Hanna Barriga (KTH / SciLifeLab)

23 Food protein superstructures on interfaces as seen by X-rays

Pulses and beans are important protein sources in the current protein transition, but much of the behavior of pulse proteins in food systems is still unknown. In particular in interface-dominated materials (emulsions, foams, etc), the nanoscopic behaviour of a protein – how they fold, stretch, and lock into place – governs whether a protein assembly ends up as a gel, a glass, or something in between.

In our lab we have used high resolution AFM to reveal the superstructures of pulse proteins on the air-water interface. While this is very insightful, such films are lifted from the interface and are dry. Scattering techniques are ideal for an in-situ analysis of pulse protein interfacial superstructures. In our recent work, we have performed different scattering experiments to glean in situ information on several hierarchical levels of protein assembly. Transmission SAXS shows how the individual protein shape is affected by adsorption to the interface, whereas in situ grazing incidence (GI)SAXS gives us a unique insight in how protein superstructures are formed during the adsorption and aging process.

Speaker: Jasper Landman (Wageningen University & Research)

10:30 ☕️Coffee

Highlights & Restart: Preparing for Restart

Conveners: Christian Pfleiderer, Prof. Martin Müller (Helmholtz-Zentrum hereon GmbH)

24 General remarks on the restart procedures

Speaker: Michael Schulz

25 Preparations of the Sample Environment Group

Speaker: Dr Manuel Suarez Anzorena (Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München (TUM))

26 SPODI, ERWIN and FIREPOD: three powder diffractometers getting ready

Speaker: Anatoliy Senyshyn

27 Small angle scattering without cold neutrons - ideas and plans

Speaker: Henrich Frielinghaus (JCNS)

28 The new Data Management workflow at MLZ

Speaker: Christian Felder

12:30 🍴Light lunch

Postersession: Discuss Science & Instruments!

29 P-77: In-situ cryogenic mechanical testing by neutron diffraction for ultra-low-temperature applications

This PhD project will investigate the mechanical behaviour of steel and aluminium alloys at cryogenic temperatures through experiments performed using neutron diffractometry with the SALSA strain diffractometer at the Institut Laue-Langevin (ILL), Grenoble. The aim is to correlate macroscopic stress–strain behaviour with lattice-scale strain evolution, providing new insights into deformation processes under ultra-low-temperature conditions.
Specimen preparation and initial laboratory characterisation will be carried out at the Technical University of Munich (TUM) and the FRM II facility, while strain measurements will be performed predominantly at the ILL. Collaboration between the ILL and additional neutron facilities, such as FRM II, will enable a more comprehensive investigation.
The research is driven by the need for materials capable of reliable performance in extreme environments, particularly for liquid hydrogen and liquefied natural gas applications that are central to the European green transition.
In summary, the project seeks to advance understanding of cryogenic deformation mechanisms and contribute to the design of alloys with improved performance in service.

Speaker: Laura Thackray (Technical University of Munich; Institut Laue-Langevin)

30 P-12: The relation of anisotropic peak broadening with lattice symmetry in powder diffraction

Lattice relaxation, i.e. small lattice symmetry lowering, could lead to unresolved peak splitting in powder diffraction, which results in anisotropic, i.e. $hkl$-dependent, peak broadening. Recently Gregorkiewitz & Boschetti [1] derived formulas for $1/d_{hkl}^2$ (with $d_{hkl}$ being an interplanar distance) for each split peak component in the six minimal relaxation schemes. Anisotropic peak broadening caused by lattice relaxation can be parameterized by the variance of those slightly dispersed peaks’ positions [2]. For all relaxation schemes the variances $\sigma^2(h,k,l)$ are expressed as fourth-order polynomials in $h, k, l$ indices [2]:

$\sigma^2(h,k,l)=\sum_{HKL}S_{HKL}h^H k^K l^L$,

with $H+K+L=4$. Popa [3] provided symmetry restrictions for each Laue class for $S_{HKL}$ coefficients. Stephens’ phenomenological model of anisotropic peak broadening [4] assumes that each crystallite in a powder sample is generally triclinic and that only the average lattice constants over the entire sample satisfy the restrictions of a given lattice symmetry. Consequently, peak broadening can also be expressed as fourth-order polynomials in $h, k, l$. However, anisotropic peak broadening caused by the lattice relaxation gives more constraints [2] between the $S_{HKL}$ coefficients as compared with those listed in [3, 4]. The seminal papers by Popa [3] and Stephens [4] and the recent paper by Gregorkiewitz & Boschetti [1] are connected by expressing the $S_{HKL}$ parameters in terms of lattice parameter increments [2].

[1] M. Gregorkiewitz & A. Boschetti, Acta Cryst. A 80 (2024) 439
[2] P. Fabrykiewicz, Acta Cryst. A 81 (2025) 245
[3] N. C. Popa, J. Appl. Cryst. 31 (1998) 176
[4] P. W. Stephens, J. Appl. Cryst. 32 (1999) 281

Thanks are due to Martin Meven (RWTH Aachen University and Forschungszentrum Jülich GmbH), Radosław Przeniosło and Izabela Sosnowska (University of Warsaw) for inspiring discussions.

Speaker: Dr Piotr Fabrykiewicz (Institute of Crystallography, RWTH Aachen University, Germany and Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Garching, Germany)

31 P-26: PLEPS (Pulsed Low Energy Positron System)

PLEPS measures the positron annihilation lifetime of atomisticdefects in various materials with a pulsed monochromatic positron-beam of variable energy.PLEPS is an ideal tool for:
a) defect-identification and defect depth-profiling in thin-layered structures of semiconductors and insulators,
b) characterization of radiation-damage in materials for fusion and fission, and
c)direct measurement of small pore-sizes in polymers, polymer layers and membranes.

Speaker: Ricardo Helm (Universität der Bundeswehr München)

32 P-66: ANTARES

Presenting the capabilities of the thermal/cold neutron imaging instrument ANTARES

Speaker: Burkhard Schillinger

33 P-64: Prompt Gamma Activation Analysis

The poster presents the capabilities of the PGAA method

Speaker: Dr Zsolt Revay (PGAA)

34 P-10: Thermogels for 3D bioprinting formed by thermoresponsive tetrablock terpolymers

Thermogels are of great interest in biomedical applications such as tissue engineering or drug delivery. For applications, the possibility to design specific thermogels with predetermined mechanical properties and tunable gel points is crucial. Tetrablock terpolymers offer numerous possibilities to tune the gel point and the gel properties for the desired purpose [1].

To determine the underlying structures, we use small-angle neutron scattering (SANS) to investigate a thermoresponsive BABC tetrablock terpolymer consisting of oligo(ethylene glycol) methyl ether methacrylate (OEGMA, “A”), n-butyl methacrylate (BuMA, “B”) and thermoresponsive di(ethylene glycol) methyl ether methacrylate (DEGMA, “C”) in aqueous solution. At sufficiently high polymer concentrations and at body temperature, these BABC polymers have shown promising gelling behavior [1,2]. Here, we address the effect of temperature at different polymer concentrations, ranging from dilute to concentrated. We find that, at room temperature, the tetrablock terpolymers form “core-satellite” type micelles with hydrophobic BuMa cores and satellites, which are linked to each other by the hydrophilic OEGMA blocks. At body temperature, the DEGMA blocks attached to the satellites are collapsed, which promotes attractive hydrophobic interactions between the satellites and drives network formation via secondary physical crosslinks.

[1] A.P. Constantinou et al. Macromolecules 2025, 58, 9122-9139
[2] A .P. Constantinou, et al. Macromolecules 2018, 51, 7019-7031

Speaker: Ms Katarina Döbler (Technical University of Munich)

35 P-50: POWTEX: High-Intensity Time-of-Flight Neutron Diffractometer for Powder and Texture Analysis

POWTEX is a TOF neutron powder diffractometer built by RWTH Aachen University and Forschungszentrum Jülich, with contributions from Göttingen University. Funded by the BMFTR (Projects 05K22PA2 and 05K23PAA), it aims to enable rapid measurements, in-situ chemical experiments and parametric studies. The wide angular coverage significantly reduces the need for sample tilting for texture analysis.

New concepts for POWTEX include two double-elliptic neutron guides with octagonal cross sections that focus the neutrons on the small sample, and a solid-¹⁰B volume detector with high efficiency and a large nine-steradian coverage. A shared focal point at the pulse chopper improves time resolution and reduces background noise from the source.

In terms of theoretical concepts, multidimensional data-reduction algorithms handling angular- and wavelength-dispersive datasets have been developed and implemented, e.g. in Mantid, plotting intensity as function of the newly introduced orthogonal coordinate system d, d⊥ as alternative to the complementary λ vs. 2θ coordinates. This very procedure, in addition to analytical instrument parametrizations based on fundamental design values, has allowed for multidimensional Rietveld-analysis using a modified version of GSAS-II for various TOF diffractometers (POWGEN@ORNL, POWTEX@POWGEN@ORNL, SNAP@ORNL) and also various samples (powdered diamond, BaZn(NCN)₂, PbNCN, Fe(dca)₂(py)₂), hence demonstrating the broad applicability of the new method.

Speaker: Noah Nachtigall (RWTH Aachen University)

36 P-16: A 100 kN Testing Machine for In-Situ Neutron Studies of High-Temperature Alloys under Mechanical and Thermal Loading

An innovative 100 kN testing machine for tensile, compression, and fatigue experiments on industrially relevant high-temperature alloys has been developed for in-situ microstructural characterization under combined mechanical and thermal loading. In addition, the system can serve as a versatile sample environment for in-situ neutron experiments at FRM II beamlines such as Stress-Spec, SPODI, Antares/Nectar and SANS-1. Neutron diffraction (ND) enables the determination of lattice parameters, phase fractions, and residual strains, while small-angle neutron scattering (SANS) provides information on the size and volume fraction of nanoscale γ′ precipitates. Cracks and their propagation can be observed via neutron imaging (NI). Deformation and heating experiments can thus be performed under realistic application conditions, allowing the material response to be probed directly in situ. For Ni-based alloys, testing temperatures above 1200 °C are achievable. Future developments include the integration of laser heating and active cooling, further broadening the experimental capabilities of the setup.

Speaker: Massimo Fritton

37 P-92: Application of the NeXus data format at MLZ

High-performance data formats, such as NeXus format, are essential for ensuring interoperability among various facilities and users. NeXus is based on the widely known HDF5 file format with the addition of domain-specific structure for data and metadata that is defined by the scientific community. This approach provides a sufficient level of data description, necessary for its understanding, analysis, re-analysis, or even full reproduction of the measurement.
MLZ is actively engaged in promoting and implementing the NeXus file format across its beamlines. In order to write data in the NeXus format, special templates will be provided in the NICOS instrument control software. Each template will define the data and metadata structure for a given instrument and technique. The work has successfully started with the NeXus template preparation for the PANDA three axes spectrometer and TOPAS time-of-flight spectrometer and will be continued for all other instruments at the facility. In this contribution, we will present our progress and future plans towards application of the NeXus data format at MLZ.

Speaker: Iryna Lypova (TUM/FRM II)

38 P-51: Applications of PaNET in Neutron Research

In order to build a comprehensive understanding of all kinds of materials, the Photon and Neutron (PaN) community has been developing an increasing portfolio of experimental techniques (ET). These techniques share similarities including physical processes, experimental probes, functional dependencies, or purposes. This intricate web of techniques benefits from organisation into an ontology, known as the Photon and Neutron Experimental Technique (PaNET) ontology.
We aim to highlight the existing and potential applications of this ontology. One notable application is the development of a beamline finder, as demonstrated for the PETRA III synchrotron. This tool aids users in identifying beamlines that align with their specific requirements of their scientific questions. The ontology facilitates this process by providing detailed information about available methods and techniques.
The techniques listed in the ontology can be integrated into experimental datasets, thus enhancing the findability of datasets and improving data accessibility. Additionally, specifying the ET during a measurement can be used to trigger metadata schemas that are tailored to a specific technique. This ensures that the captured metadata is relevant and precise, enhancing the quality and utility of the data.
We present an overview of the current status of these activities, with ideas on how you can benefit from them and the opportunities for direct involvement.

Speaker: Melanie Nentwich (DGK)

39 P-31: Background from sample cryostat on three-axis spectrometer: can it be reduced?

Background from sample cryostat on three-axis spectrometer: can it be reduced?

A.Ivanov, A.Piovano
Institut Laue-Langevin, Grenoble, France

Background from sample environment may be a relatively important issue in the measurements with small and low scattering samples on a three-axis spectrometer. It can be present in the form of sharp peaks as a function of nominal energy transfer E and scattering wave vector Q. The intensity of this parasitic intensity can be well comparable to the measured inelastic signal. The complex Q-E structure of such background stemming from sample environment such as cryostats arises largely due to multiple elastic scattering (diffraction) of the incident beam on the internal structure of a cryostat comprising several temperature screens and walls of vacuum vessels even if they are made as a rule from relatively low scattering aluminium alloys. We show at the thermal TAS-IN8 (ILL) that this parasitic scattering can be reduced by introducing neutron absorbers inside the cryostat, in the most internal volume, on the side opposed to the used scattering side. This will imply rotating the sample with the sample stick, independently of the static cryostat thus changing the “classical” mode of operation. In fact, such systems are already being routinely used at ILL with different sample environments such as cryomagnets, for instance. If combined with a single crystal alignment device Goniostick developed at ILL, the experimenters recuperate the full flexibility of the sample movements inherent to measurements on three-axis spectrometers - now with reduced background that stems from sample environment.

Speaker: Alexandre IVANOV (Institut Laue-Langevin, Grenoble)

40 P-67: Beam focusing with nested mirror optics(NMO) at RESEDA

The RESEDA(REsonance Spin Echo for Diverse Applications) instrument is a spectrometer that can use the MIEZE(Modulated IntEnsity with Zero Effort) method, a variant of neutron spin echo(NSE) that uses radio frequency(RF) spin flippers instead of static magnetic fields and that can measure samples that depolarize the beam.
As a next step for improving the experimental setup it was proposed that nested mirror optics should be integrated to focus the beam at various components of the instrument.
Focusing the beam at the sample might allow measurements of samples with smaller sizes, such as samples in a diamond anvil cell. It also might allow for measurements at higher scattering angles, as it could reduce phase aberrations for the MIEZE method.
Focusing the beam at the RF-flippers allows to build smaller AC-coils, leading to higher accessible frequencies, and consequently might lead to a better energy resolution of the spectrometer.
In order to create an efficient setup that does not introduce additional artifacts, careful consideration of all effects caused by inserting NMO is necessary.
Here we will present preliminary results of the simulations of NMO integration and discuss their potential.

Speaker: Florian Schoenleitner (TUM)

41 P-63: Comparing neutron experimental data of water absorbed to cellulose to simulations

Neutron scattering experiments provide valuable insights into the nanoscopic properties of matter. In this contribution we study water absorbed to cellulose leading to the conclusion that water absorbed to cellulse is adherend with its hydrogen bonds fixed to the cellulose, indicating that steric effects play only a minor role.
The time- and lenghtscales probed by neutron scattering experiments are also accessible through molecular dynamics (MD) simulations. If the simulations reproduce the experiments, they can give further insight into the material properties on the nanoscopic scale.
MD simulations were created for water with partially fixed water molecules at different temperatues to compare it to experiemental data of water absorbed to cellulose. The fixed water molecules served as minimalistic hydrogen bond donors and acceptors such as the OH groups on cellulose.
The simulations were first evaluated for their soundness followed by a comparison to the experimental data.
We observe a decline of the diffusion coefficient the more water molecules are fixed and the colder the simulated water is.
The comparison of simulation and experimental data shows a generell agreement of the data regarding the structure. While the agreement of simulation and experiment concering the dynamics is good, differences become apperent at smaller Q-values, i.e. longer real space distances.

Speaker: Mrs Veronika Reich (GEMS at MLZ, Helmholtz-Zentrum Hereon)

42 P-85: Crosslinking Mechanisms of Alginate-based Graft Copolymers with Thermoresponsive Side Chains

Alginates are naturally occurring polysaccharides found in brown algae. Featuring non-toxicity and highly controllable ionic gelation by divalent metals, such as Ca2+, alginates have seen extensive use in biomedicine, such as wound dressings and in 3D bioprinting.

Here, we investigate an alginate-based graft copolymer, namely Alginate-g-P(NIPAM94-co-NtBAM6), where a random copolymer of N-isopropylacrylamide (NIPAM) and N-tert-butyl acrylamide (NtBAM) is grafted onto sodium alginate backbones. While introducing thermoresponsive PNIPAM enables temperature-induced gelation, the hydrophobic NtBAM regulates the transition temperature by varying the water solubility of the side chain. The internal structure and the gelation mechanisms of the alginate-based copolymers are studied in dilute and concentrated aqueous solutions, also in the presence of Ca2+, using small-angle neutron scattering (SANS) at instrument SANS-I at the Paul-Scherrer-Institute. At this, contrast matching of the backbone and the side chains was used to obtain specific structural information.

The SANS data show increasing forward scattering signal during thermal- or ionic-gelation, which is attributed to the crosslinking between the alginate backbone and the PNIPAM side chains. While both gelation approaches coexist in the brush solution, index matched measurements have demonstrated that temperature-induced transition is achieved independently via the association of the side chain.

Speaker: Wenqi Xu (Technical University of Munich, TUM School of Natural Sciences, Soft Matter Physics Group)

43 P-14: Data Management at MLZ

Data management at the Heinz Maier-Leibnitz Zentrum (MLZ) has seen substantial advancements in recent years, particularly during reactor downtime. This has enabled us to prioritise developing MLZ's digital infrastructure. A notable enhancement is the integration of a Single Sign-On (SSO) system, enabling users to access data services using their existing User Office (GhOST) credentials. Experimental metadata is now captured seamlessly online during measurements via the Networked Instrument Control System NICOS, ensuring consistency and completeness. Raw data and associated metadata are systematically stored and made accessible via the SciCat metadata catalogue, facilitating efficient data discovery, sharing, and long-term preservation. These developments significantly improve the user experience and lay a robust foundation for future digital scientific workflows at the MLZ.

Speaker: Christian Felder

44 P-93: Data Reduction with the MIEZEPY software

MIEZEPY is an open-source software package designed for the efficient reduction of data acquired in the MIEZE (Modulation of Intensity with Zero Effort) mode. MIEZE is a neutron resonant spin echo technique that enables the measurement of the intermediate scattering function, S(Q, τ), in depolarizing sample environments, such as under high magnetic fields. This technique is implemented at the RESEDA (Resonance Spin Echo for Diverse Applications) spectrometer at MLZ, which offers sub-µeV energy resolution and an exceptional dynamic range (~8 orders of magnitude). As part of its commitment to making data FAIR, MLZ is preparing to switch to the NeXus data format in the near future. Initial steps towards implementing the new data format include drafting a NeXus template for raw data recording in NICOS and enabling NeXus file readout in MIEZEPY for subsequent data reduction and analysis. Further progress in this transition is expected in the coming months.

Speaker: Iryna Lypova (TUM/FRM II)

45 P-89: Deep Learning-Driven GISAXS Data Processing for Nanostructure Characterization

Grazing-incidence small-angle X-ray scattering (GISAXS) has emerged as a uniquely powerful technique for elucidating surface and near-surface morphologies over length scales from roughly 1 nm to 1 µm. Yet, extracting quantitative structural parameters from GISAXS data requires solving an inverse problem: one must assume a structural model, simulate its scattering response, and iteratively refine model parameters through curve-fitting routines. This process can extend over hours or days per dataset, demands expert intuition to select and constrain models, and may converge to local minima, limiting throughput and reproducibility.

Recent developments in machine learning (ML) and deep neural networks present a promising alternative, capable of learning direct mappings between observed scattering patterns and underlying structural descriptors without explicit model fitting. In domains such as X-ray crystallography phase retrieval and transmission small-angle scattering, ML has demonstrated rapid classification, denoising, and parameter extraction capabilities. However, applications to two-dimensional GISAXS inversion are still in its infancy. A major enabling factor in GISAXS lies in the ability to generate large, labeled training datasets via forward simulations based on first-principles physics. By sampling broad parameter spaces of particle geometries, interparticle spacings, disorder metrics, and experimental artifacts, one can train supervised learning models to generalize to real experimental data, potentially delivering real-time analysis.

Here, we present a dual-branch convolutional neural network (CNN) framework designed to fully automate GISAXS data inversion, simultaneously retrieving (1) the particle size distribution, as a discretized probability density function representing particle dimensions (form factor), and (2) interparticle correlation parameters, namely average center-to-center distance and positional disorder (structure factor). Our approach integrates physics-based simulation, data preprocessing, and modern deep learning architectures to achieve millisecond-scale inference on standard computing hardware.

Speaker: Yufeng Zhai (DESY)

46 P-01: Deep-Learning Approaches for Noise Removal in Neutron Imaging

Neutron imaging provides a powerful means to investigate samples in real space. At the FRM II, the ANTARES instrument represents a state-of-the-art facility for such studies. However, due to direct viewing of the source and secondary processes, a considerable number of gamma particles reach the detector. These contribute significantly to noise and degrade the overall measurement quality.

The currently employed algorithm Find&Replace relies on user-defined parameters and requires substantial computational time. To address this limitation, we propose a supervised deep learning approach as a replacement. Several established neural network architectures are presented, and we introduce a dedicated data pre-processing strategy tailored to the characteristics of neutron imaging data.

As this study is ongoing, only preliminary results are presented. Nonetheless, the findings already indicate a clear improvement compared to the status quo, demonstrating the potential of supervised learning to advance neutron imaging analysis at ANTARES.

Speaker: Abdel Rahman Al-Falou

47 P-23: Development of a new Macromolecular Instrument at the High Brilliance Neutron Source in Jülich

A selene type, 20 m long instrument has been proposed on the 96 Hz moderator which could serve as a future macromolecular diffractometer for single crystals (e. g. protein crystals). A macromolecular diffractometer at the 24 Hz TMR station with a conventional neutron guide of 80 m length using a cold moderator is planned to be designed and simulated. A traditional elliptical neutron guide is considered to shape the beam spot and the divergence for the instrument, since the typical biological sample size is very small, sometimes between 0.01 mm3 and 1 mm3. An optimized neutron guide for the latter instrument should be developed and its performance should be compared to the 20 m long instrument. While this might lead to worse background conditions and requires a significant beamline shielding, it would add the flexibility to use a pulse shaping chopper. It is simulated that the 80 m instrument has twice the flux and a 1.5 times better resolution in reciprocal space of the 20 m instrument in a wavelength band of 2-4 Å.

Speaker: Jialian He (Forschungszentrum Jülich GmbH)

48 P-27: Diffractometer ERWIN

Diffractometer ERWIN

Speaker: Markus Hoelzel

49 P-76: DNS: Polarised diffuse neutron scattering instrument with time-of-flight inelastic scattering option

Presenting instrument DNS, a polarised diffuse neutron scattering instrument with time-of-flight inelastic scattering option

Speaker: Dr Yixi Su (JCNS-MLZ)

50 P-30: Effect of mechanical pressure on the lithiation heterogeneity in large-format pouch-type Li-ion batteries

Lithium-ion pouch cells are one of three cell geometries frequently employed in electric vehicles due to their high energy density and flexible design [1,2], enabling high gravimetric and volumetric energy density. However, their performance and degradation are highly sensitive to external mechanical stabilisation, where stack pressure strongly influences lifetime and safety [3]. In this study, the electrochemical ageing of large-format pouch cells was systematically investigated under different pressure conditions using long-term cycling and synchrotron powder diffraction radiography. Unconstrained cells delivered the highest initial depth of discharge but suffered from rapid capacity fade, fast resistance growth, elevated temperature, and shortened lifetime. Constrained cells, in contrast, exhibited reduced accessible capacity but significantly improved cycle life, stabilised resistances, and lower thermal stress. At high pressure, transport limitations were dominating, while moderate pressure balanced cell stability and performance. Diffraction results revealed homogeneous lithiation in fresh cells, but ageing induced strong inhomogeneities. High pressure led to doughnut-shaped lithium profiles with central depletion and edge enrichment, attributed to reduced porosity, increased tortuosity, and electrolyte redistribution. The results establish a direct link between mechanical pressure, degradation, and lithiation heterogeneity, highlighting moderate pressure as the optimal regime for long-term pouch cell operation.

References:
[1] Yoshino, A., Angewandte Chemie International Edition, 51(24), 2012 (DOI: 10.1002/anie.201105006).
[2] Gröger, O., et al., Journal of The Electrochemical Society, 162(14), 2015 (DOI: 10.1149/2.0211514jes).
[3] Schommer, A., et al., Journal of Power Sources, 629, 2025 (DOI: 10.1016/j.jpowsour.2025.236019).

Speaker: Tobias Hölderle

51 P-47: Electron Microscopy – a complementary technique with neutron scattering

Electron microscopy (EM) is a powerful imaging technique that use an electron beam to illuminate a sample, making it particularly valuable in the study of soft matter.
Transmission electron microscopy (TEM) allows real-space investigations to obtain knowledge about particle shape, size, size distribution, self-assembly, and aggregation. Scanning electron microscopy (SEM) with environmental mode (ESEM) allows the study of samples in their natural state. With a wide selection of detectors, a temperature-controlled stage, and three vacuum modes (high-, low- vacuum, and ESEM), the complex study of a broad variety of samples is possible.
The JCNS Transmission Electron Microscopy laboratory offers preparation, e.g., plunge freezer or ultramicrotome, and investigation of the samples to users who wish to support their neutron experiments done at the MLZ using (Cryo-) TEM or ESEM.
The TEM and SEM instruments will be presented, as well as the equipment for sample preparation.

Speaker: Joanna Michalska-Walkowiak (Jülich Centre for Neutron Science (JCNS) at MLZ, Forschungszentrum Jülich GmbH, Garching, Germany)

52 P-39: Eutectic intermediate phase in the ternary complex hydride system

Hydrogen storage in light hydride systems for mobile applications is a widely discussed but a highly controversial topic because of explosive mixtures of hydrogen with oxygen. This danger, however, is eliminated, if hydrogen is stored in complex hydrides, releasing hydrogen only under significant heat impact.

The main issue for complex hydride mixtures is the kinetics of the reversible reaction with hydrogen. One of prospective candidates is 6$\mathrm{Mg(NH_2)_2}$:9LiH, promptly interacting with hydrogen when doped with $\mathrm{LiBH_4}$. Increase of $\mathrm{LiBH_4}$-quantity results in a more significant improvement of the reactions with hydrogen. The catalytic impact of $\mathrm{LiBH_4}$ is explained by the formation of low-melting intermediate phases with high Li-ion conductivity: a metastable $\mathrm{Li_2BH_4NH_2}$ and a peritectically melting $\mathrm{Li_4BH_4(NH_2)_3}$.

In the $\mathrm{LiNH_2-LiBH_4}$ equilibrium phase diagram, the eutectic point, i.e. a mixture with the lowest melting temperature, is located at the 1:2 ratio and 90$\mathrm{^{o}}$C. This eutectic mixture was characterized by various techniques, including neutron total scattering. Its intrinsic structure under the reaction conditions was elucidated by EPSR, which gave a hint about its role as a liquid-phase catalyst in the corresponding hydrogen storage composition (6$\mathrm{Mg(NH_2)_2}$:9LiH:6$\mathrm{LiBH_4}$ or, as reported in literature, 6$\mathrm{Mg(NH_2)_2}$:9LiH:12$\mathrm{LiBH_4}$).

Speaker: Anastasiia Kuznetsova (WPN Hereon Garching branch)

53 P-35: EvalSpek-ML – Automation of Spectral Analysis for PGAA

Analysis of the spectra obtained with Prompt Gamma Activation Analysis (PGAA) is a well-developed method with relatively straightforward data treatment. However, due to the large number of gamma rays emitted after neutron capture, and the possible interference of the gamma rays from different elements, in the target material, this process can be time consuming. This is also additionally complicated by the fact that the peak shape in PGAA is influenced by several contributions, requiring careful analysis. Expert analysis can mitigate some of these problems, but there are situations when the analysis can get so complex that it is hard to achieve the necessary quality in identifying and quantifying the elements present in the target material in a reasonable time.
Within EvalSpek-ML project, funded by BMBF (Grant number: 05D2022), application of machine learning (ML) algorithms is explored for automation of various spectral types analysis. Overview of the research within the project will be presented, with the special focus on the PGAA spectra. Various ML approaches and results will be presented, as well as the discussion of custom metrics and simulations. Custom metrics are included to compare ML analysis, at least to a degree, with the expert one, while the simulations are introduced to mitigate the problem of the number of spectra required for successful training of the algorithms.

Speaker: David Knezevic (TUM-FRMII)

54 P-45: Fast neutron gamma-ray spectrometry (FaNGaS) for elemental analysis

Neutron analytical methods are indispensable tools for non-destructive elemental analysis of materials or items of various origins (geological, environmental, biological, cultural, archeological and industrial). Fast neutron inelastic scattering brings analytical capabilities to a new level, allowing to analyze thick and dense samples thanks to higher incident energy of neutrons via (n,n’,gamma) reactions. FaNGaS (Fast Neutron Gamma-ray Spectrometry) instrument installed at the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching is a new instrument that uses fission neutrons delivered by the SR10 beam tube of the FRM II reactor allowing measurement of small to large samples up to 400 cm3 in volume. Another important application of FaNGaS instrument is measurement of partial prompt gamma-ray production cross-sections of (n,n’,gamma) reactions, contributing to extend and improve nuclear data. Coupling of FaNGaS with advanced fast neutron techniques such as fast neutron imaging and transmission techniques broadens the range of analytical capabilities for qualitative and quantitative analysis of nonhomogeneous samples. Coupled with fast data processing algorithms based on modern machine learning tools large measured data streams from bulk and voluminous samples can be analyzed online, making such fast neutron-based analytical technology promising in a wide range of tasks for industrial applications (e.g. ore, coal, magnetic material waste streams etc).

Speaker: Iaroslav Meleshenkovskii (JCNS FZ-Juelich)

55 P-22: FIREPOD: A new thermal high-throughput powder diffractometer at MLZ

The new instrument FIREPOD (FIne REsolution POwder Diffractometer) was successfully transferred from Berlin to Garching as part of a BMBF-funded project. At the MLZ,it will have a ‘second life’ as a dedicated high-throughput instrument, ideally suited for a wide range of fast parametric studies and studies with large sample series. As such, it perfectly complements the group of three unique thermal powder diffractometers located at the SR8 beam tube of the FRM II. Due to the optimised design of the detector, even very bulky sample environments can be used. The scientific focus will be on advanced materials research, including topics with promising industrial applications such as batteries, hydrogen storage, or construction and functional materials under a wide range of conditions, particularly in situ and in operando studies. The details of the instrument design to meet these goals and its forseen capabilies will be presented in detail.

Speaker: Christoph Hauf

56 P-02: GISANS and GIXS of Slot-Die Coated Perovskite Quantum Dot Thin-Films

Perovskite Nanocrystal Solar Cells (PNCSC) hold great promise for future renewable energy solutions. Utilizing Perovskite Nanocrystal Layers as the active layer in solar cells exploits quantum confinement, if the crystal size is below the Bohr radius [1], resulting in high power conversion efficiencies, a high photoluminescence quantum yield (PLQY), a narrow photoluminescence (PL) peak, and enhanced stability compared to bulk perovskite.[1] To ensure that the nanocrystal size is stabilized, so-called ligands are attached during synthesis as organic compounds. The versatility of X halides (I-, Br-, Cl-) and A cations (FA+, MA+, Cs+) allows precise bandgap control across the visible spectrum of the ABX3 perovskite structure.[2]
This study focuses on Cesium Lead Iodide (CsPbI) and Formamidinium Lead Iodide (FAPbI) perovskite nanocrystal layers. Grazing incidence x-ray scattering (GIXS) is used to reveal crystal structure and texture. Because X-rays primarily probe the crystals, GISANS provides complementary sensitivity to the organic ligands due to their different contrast. By combining both techniques, a comprehensive understanding of the PNC thin film, including its crystals and ligands, is obtained.

[1] L. Liu et al., Adv. Sci. 9.7, 2104577 (2022)
[2] L. Protesescu et al. Phys. Nano. Lett. 15.6, 3692–3696 (2015)

Speaker: Thomas Baier

57 P-46: HEiDi

Presenting instrument HEiDi, a hot neutron single crystal diffractometer

Speaker: Dr Martin Meven (Forschungszentrum Jülich GmbH, JCNS-4)

58 P-17: Hierarchical self-assembly of reflectin studied by SANS, QENS, and NSE

The structural color change of cephalopods is primarily driven by the self-assembly of reflectin proteins, which modulates the refractive index of the Bragg reflection layer, thereby altering the propagation of light. Additionally, when induced by small molecules like imidazole, reflectin will undergo higher-order assembly, forming a hexagonal lamellar structure. This work employs small-angle neutron scattering (SANS), quasi-elastic neutron scattering (QENS), and neutron spin-echo (NSE) techniques to investigate the structural and dynamic changes in reflectin assembly. Specifically, we examined the effects of temperature, sample concentration, and small molecules on the self-assembly process of reflectin.
After analysis, we found that: i) As the temperature increases, the structure of the protein becomes more compact, while all its dynamic motions are enhanced. ii) As the protein concentration increases, the protein structure becomes more compact. The addition of imidazole prevents the protein structure from becoming more compact as concentration increases. iii) The addition of imidazole enhances large-scale spatial motions while suppressing small-scale spatial motions. The enhancement in dynamics at large scale is attributed to the larger-scale motions associated with the high-order self-assembly of reflectin. The results will contribute to establishing a more precise and well-defined mechanism of reflectin self-assembly at the molecular level, providing a theoretical foundation for advancing applications of this color-changing behavior.

Speaker: LING GUO (City University of Hong Kong)

59 P-81: High Accuracy Optical Feedback System for Robotic Sample Manipulation at STRESS-SPEC

Materials and components with intricate geometries, such as from additive manufacturing (AM), require highly flexible sample positioning systems during diffraction experiments. Therefore, the STRESS-SPEC group at Heinz Maier-Leibnitz Zentrum (MLZ), Germany, has pioneered the use of industrial robots [1, 2] to enhance sample handling and positioning at neutron diffractometers. While these robots may easily position the sample in the desired directions and orientations, their absolute accuracy of up to ±0.5 mm has been insufficient for precise local measurements. To allow accurate full strain tensor determination and accurate centering of local texture measurements, a positioning accuracy within 10% of the gauge volume size is required, which may be as small as 1 mm³ on modern neutron diffractometers [3]. To address this limitation, we have upgraded the STRESS-SPEC robotic system with an optical metrology setup that actively tracks and corrects the sample position with a spatial accuracy of better than 50 μm. We will present the complete measurement process chain and verification steps for this improved sample positioning system.
Furthermore, a versatile laser furnace with a large neutron acceptance angle for temperatures up to 1200°C and a lightweight tensile testing machine are currently being built to be mounted on the robot flange. Together with the optical feedback system, the most common experimental scenarios are covered in a semi-automated measurement environment.
[1] H.-G. Brokmeier et al., Mater. Sci. For. 652 (2010) pp. 197–201. DOI: 10.4028/www.scientific.net/MSF.652.197
[2] C. Randau et al., Nucl. Instr. Meth. A 794 (2015) pp. 67–75. DOI: 10.1016/j.nima.2015.05.014
[3] R. Ramadhan et al., Nucl. Instr. Meth. A 999 (2021) 165230. DOI: 10.1016/j.nima.2021.165230

Speaker: Lijiu Wang

60 P-70: High-resolution neutron powder diffractometer SPODI

The instrument state-of-the-art along with the startup activities will be presented.

Speaker: Anatoliy Senyshyn

61 P-69: Homogeniety of A6061 RAM aluminum manufactured with laser power bed fusion

Laser Powder Bed Fusion (LPBF) is an established technique for additive manufacturing. However, not all alloys are manufacturable with LPBF. Especially high-strength aluminum alloys that can be precipitation hardened are difficult to weld and thus difficult to process with LPBF. The growth of elongated grains and build-up of residual stress lead to anisotropic macroscopic mechanical properties of the printed part and higher risk of crack formation at grain boundaries. Processing at elevated environment temperatures can reduce the problems but is not economical due to long cooldown times. To mitigate these problems the relatively new approach of reactive additive manufacturing (RAM) is being investigated in cooperation of Colibrium Additive, Friedrich-Alexander-Universität Erlangen-Nürnberg and Technical University of Munich.
Here reactive particles are mixed with the pre-alloyed aluminum powder that react exothermally during melting and form ceramic nanoparticles that inhibit grain growth and act as nucleation points to form smaller grains and therefore reduce cracking.
To assess the bulk microstructure and distribution of RAM particles neutron imaging studies were performed on samples printed with different process parameters using different laser powers.
Both transmission and dark-field contrast from neutron grating interferometry were used to show the homogeneity of the printed parts.
Due to the high boron content in the added RAM particles their distribution can be seen in transmission contrast.
The sensitivity of the dark-field signal to scattering of micrometer-sized structures enables the spatially resolved assessment of defects like porosity and anomalies such as unreacted RAM particles.

Speaker: Simon Sebold (MLZ)

62 P-20: HYMN – A novel unified toolbox for in-situ magnetic hyperthermia experiments using neutron scattering

Magnetic nanoparticles (MNPs) offer a promising avenue for magnetic hyperthermia, a cancer therapy where MNPs are introduced into tumors and then heated with an external magnetic field to destroy cancer cells. For this clinical application to be safe and effective, it's critical to optimize the magnetic field parameters and the heating power. Since safety concerns limit the maximum applied magnetic field amplitude and frequency, improving heating power can be achieved mostly by optimizing the MNP structure itself. An ideal tool for characterising such MNPs is small angle neutron scattering (SANS). Our ERUM-Pro HYMN project aims to develop a novel, unified experimental and computational toolbox for in-situ magnetic hyperthermia experiments under clinical conditions, utilising SANS. This will be achieved by developing two custom-made setups: one AC field generator for operation at the beamline (up to 20 mT at 50-1000 kHz at the sample position) and an accompanying AC Susceptometer, for sample precharacterisation. We also present the progress on the design of these setups and first calibration measurements.

Speaker: Luisa Gorgas (Technical University of Munich)

63 P-41: Imaging from meV to MeV Neutrons at the NECTAR Instrument

Located at the SR10 at the FRM II, NECTAR is a versatile instrument and designed for the non-destructive inspection of various objects by means of fission neutron radiography and tomography. Compared to the Z-dependency of X-ray and gamma imaging, fission neutrons have the strong advantage of often providing similar contrast for heavy and light materials. Only few facilities around the world provide access to well collimated fast neutrons, with NECTAR at the FRM II being the only instrument that has a dedicated user program for fast neutron imaging. Aside from fast neutrons, thermal neutron as well as gamma imaging is possible by using different scintillator materials with the same detector system, extending NECTAR’s imaging capabilities to different modalities.
Here, we present the most recent upgrades to the NECTAR beam-line, including unparalleled elemental imaging capabilities as well as recent progress in event-mode imaging with fast neutrons.

Speaker: Adrian Losko (Technische Universität München, Forschungs-Neutronenquelle MLZ (FRMII))

64 P-86: Insight into SEI formation and dendrite growth in all-solid-state lithium metal batteries by Operando nWAXS

Composite solid polymer electrolytes (CSPEs) have emerged as promising candidates for next-generation all-solid-state lithium batteries (ASSLBs). However, the limited ionic conductivity and poor interphase stability have seriously hindered their practical application. Herein, the anion-trapping layered double hydroxide (LDH) was introduced to simultaneously enhance ionic conductivity and interfacial compatibility in poly(ethylene oxide) (PEO)-based CSPEs for stabilizing lithium metal anodes. The optimized composite electrolyte significantly enhances lithium-ion transport and deposition behaviors, resulting in a uniform Li+ flux distribution and consequently homogeneous lithium plating. As a result, the Li||Li symmetric cell achieves exceptional cycling stability and superior overpotential. Importantly, operando nano-focus Wide-angle X-ray scattering (nWAXS) was employed to spatially map the distribution of both the solid electrolyte interphase (SEI) layer and lithium dendrites across micron-scale lateral and vertical dimensions. The results indicate that the LDH-enhanced composite electrolyte not only effectively suppresses the growth of lithium dendrites by ensuring a uniform lithium-ion flux distribution but also enables the formation of a superior multifunctional SEI. Therefore, this study provides a novel strategy for designing high-performance CSPEs with stabilized interfaces and establishes an innovative approach for real-time visualization of SEI evaluation and dendrite growth in ASSLBs.

Speaker: Yingying Yan (Lehrstuhl für Funktionelle Materialien, Physik-Department, TU München)

65 P-59: Investigating the degradation in 21700-type cylindrical cells with neutron scattering and complementary techniques

Larger battery cell formats increase usable energy but promote inhomogeneities that affect degradation. This work examines aging in 21700-type cells with NCM cathodes and graphite/SiOx anodes using cyclic aging combined with in operando neutron diffraction, neutron depth profiling, and X-ray computed tomography. Prolonged cycling leads to Li loss, visible on the cathode through reduced NCM unit cell expansion and on the anode by suppressed formation of fully lithiated LiC₆. Differential voltage analysis reveals both loss of active anode material and Li inventory, corroborated by diffraction data showing the LiC₆ and LiC₁₂ transitions shifted to lower capacity values. Li concentration profiles confirm cathode depletion, while elevated anode Li content indicates increased solid–electrolyte interphase formation, consistent with cathode-derived Li consumption at the anode. Spatially resolved X-ray imaging analysis shows stronger degradation in the cell center than at the bottom edge, underscoring the role of electrode inhomogeneities in large-format cells.

Speaker: Thien An Pham

66 P-18: Investigation of bound coherent neutron scattering lengths using powder Bragg Diffraction

The coherent scattering length $ b_c $ is a fundamental property for many neutron techniques, but have to be determined for each nuclide individually. Although this has carefully been done over decades and results were summarized in established standard tables, some $ b_c $ values have large experimental uncertainties, including possible systematic errors, or have not been determined experimentally at all.

We therefore decided to take advantage of modern neutron powder diffraction (NPD) and to redetermine bound coherent scattering lengths bc of important isotopes, in particular those often used for isotopic substitution, e.g. to obtain scattering-length contrast or to avoid strong neutron absorption. Although other techniques such as neutron interferometry may be more precise under ideal conditions, we have found in a systematic study that neutron powder Bragg diffraction is a practical, powerful, and reliable technique that can achieve uncertainty levels of 1% or less and is even applicable on sub-gram samples with modern high-flux instrumentation.

Among others, we will present updated $ b_c $ values for all seven natural Nd isotopes, for $ ^{141}$Pr, and for $ ^{147/148/150/152}$Sm, of which some have never been determined experimentally before, as well as carefully redetermined values for $ ^{6/7/nat}$Li being of particular interest for modern battery research.

Speaker: Florian Gehlhaar (Forschungszentrum Jülich)

67 P-55: Ion-transport in battery relevant polymers - challenges in analysis

Li metal-based batteries are foreseen as future energy storage devices. However, a major hindrance to their industrial application is the uneven Li deposition on the anode that results in dendritic growth and poor columbic efficiency (CE).

Our previous work had revealed that batteries with a mechanically rigid M1I0 polymer coating on anode show a comparatively lower CE than those with a a viscolelastic M1I3 polymer coating [1]. Moreover, while anodes with M1I0 polymer coatings still showed Li dendrite growth, those with M1I3 polymer coating had smooth and homogeneous Li deposition.

In this work, we try to further study these polymers to understand the interplay between polymer dynamics and CE in batteries and the influence of Li salt. The polymer network in these polymers consists of a PFPE backbone interconnected by urethane units containing H-bonds, with H atoms involved in N-H bond being responsible for polymer rigidity.

When Li salt is added, Li cations bind to the oxygen atoms in the urethane units. In fact, FTIR revealed a lengthening of the C=O bond on addition of Li salt, which was attributed to weakening of H-bond, as Li cation formed Lewis acid complexation with the basic carbonyl oxygen site. This interaction is known also to increase barrier heights to rotation.

At the highest energy resolution QENS revealed localized dynamics in all polymers. Amongst other fast motions, these could be a due to constrained motions of the hydrogen-bonded units. While the extracted correlation times for M1I0, M1I3 and Li_M1I0 are similar, the correlation time for Li_M1I3 was twice as long. A similar trend is observed at the intermediate resolution.

Interestingly, at the lower energy resolution which probes slightly faster dynamics, the pristine polymers still show localized motions, whereas polymers with Li salt show diffusive motions. At these temporal scales, H-bond breaking is possible which may result in decoupling of Li-ions, facilitating thereby cation migration, also across the hydrogen-bond connected chains (intrachain migration).

The QENS signal contains a significant coherent contribution which limits the accessible Q-range for incoherent dynamics. At Q values below 1 Å-1, we account for the coherent contribution with a linear background. However, at higher Q values, we require characterizing the ratio of incoherent to coherent via polarisation methods.

[1] Z. Huang, S. Choudhury, N. Paul, et. al. Adv. Energy Mater. 12 (2022) 2103187

Speaker: Dr Neelima Paul (Technical University of Munich, Heinz Maier-Leibnitz Zentrum (MLZ))

68 P-32: Jülich Neutron Agent (JüNA): Neutron Research with Agentic AI

Over several decades of research in neutron experiments and methods, the Jülich Centre for Neutron Science (JCNS) has accumulated extensive knowledge, including scientific papers, manuals, Wikipedia-style articles, in-house developed software, and electronic lab notebooks. However, effectively accessing and utilizing these resources remains challenging. At the same time, high-fidelity simulation codes for neutron scattering such as VITESS [2] and Crystal Scatter [3] are extremely powerful but require substantial domain knowledge to use effectively.

In order to lower this entry barrier, we develop the Jülich Neutron Agent (JüNA), an overarching agentic AI framework designed to assist neutron scientists in their daily tasks. JüNA leverages LLMs enhanced with reasoning and action capabilities (ReAct [1]) and tool invocation via a Model Context Protocol (MCP) server, enabling AI-supported knowledge discovery, experimental design, and code generation in neutron science. One scope within JüNA focuses on chatbot-guided AI agents that assist users in parameterizing and running complex simulations without requiring deep expertise in the underlying theory or code.

As a first implementation, we focus on AI-assisted simulation software agents within JüNA. The VITESS AI Agent integrates with the open-source VITESS package for simulating neutron scattering experiments, while the Crystal Scatter Chatbot supports the high-performance small-angle scattering software Crystal Scatter.

Preliminary results demonstrate that embedding these domain-specific agents into JüNA significantly lowers the barrier to entry for neutron scientists and enhances accessibility of JCNS’s extensive knowledge base. This approach also paves the way for future AI-driven experimentation and autonomous laboratory workflows leveraging large language models, positioning JüNA as a foundation for next-generation neutron science research.

[1] Yao, Shunyu, et al. "React: Synergizing reasoning and acting in language models." International Conference on Learning Representations (ICLR). 2023

[2] https://vitess.fz-juelich.de

[3] Wagener, M., & Förster, S. (2023). Fast calculation of scattering patterns using hypergeometric function algorithms. Scientific Reports, 13(1), 780

Speaker: Ahmad Zainul Ihsan (JCNS, Forschungszentrum Jülich GmbH)

69 P-57: KOMPASS: The polarised triple-axis spectrometer (TAS)

KOMPASS, a polarised triple-axis spectrometer (TAS), is one of the most recently built instruments at the FRM II. It is designed exclusively for polarised neutrons, benefiting from its uniquely designed polarising guide setup, which consists of static and exchangeable sections. The static part of the guide system hosts a series of three polarising V-cavities, yielding a highly polarised beam. The exchangeable straight and parabolic front-end sections of the guide system enable the instrument's resolution to be adapted for experiments, offering superior energy and Q resolutions compared to conventional guide and instrument concepts [1,2,3].
The secondary spectrometer offers exceptional flexibility, enabling fully and half-polarised measurements, with or without energy analysis. At the sample table, KOMPASS provides optimised options for spherical neutron polarimetry (SNP) using CryoPAD as well as XYZ polarisation analysis. While it is conceptualised as a primarily cold-neutron spectrometers its flexible guide setup and especially its highly polarised beam even at short wavelengths makes it an excellent choice also for diffraction studies on complex magnetic structures [3]. Potential science cases include for example helical orders, systems with small ordered moments, q=0 magnetic orders such as ferromagnets or more interestingly, the recently discovered family of altermagnets, which all rely on magnetic polarisation analysis to either determine magnetic moment directions directly or to disentangle nuclear and magnetic scattering to make small moments detectable.
We will discuss the elastic and inelastic capabilities of KOMPASS when the FRM-II is operated without the cold source.

[1] M. Janoschek et al., Nucl. Instr. and Meth. A 613 (2010) 119.
[2] A. C. Komarek et al., Nucl. Instr. and Meth. A 647 (2011) 63.
[3] D. Gorkov et al., Nucl. Instr. and Meth. A 1080 (2025) 170719

The construction and development of KOMPASS are funded by the BMBF through Verbundforschungsprojekt 05K19PK1.

Speaker: Alexander Petsch (Universität zu Köln)

70 P-15: KWS-1 SANS instrument

Feasible KWS-1 modes and experiments will be presented for the period of reactor operation without the cold source.

Speakers: Henrich Frielinghaus (JCNS), Zakaria Mahhouti (Forschungszentrum Jülich)

71 P-60: KWS-3 very small-angle neutron scattering focusing diffactometer at MLZ

KWS-3 is a very small angle neutron scattering diffractometer operated by JCNS at Heinz Maier-Leibnitz Zentrum (MLZ) in Garching, Germany. The principle of this instrument is one-to-one imaging of an entrance aperture onto a 2D position sensitive detector by neutron reflection from a double-focusing toroidal mirror. In current state, KWS-3 is covering Q-range between 3·10-5 and 2·10-2 Å-1 and used for the analysis of structures between 30 nm and 20 μm for numerous materials from physics, chemistry, materials science and life science, such as alloys, diluted chemical solutions, hydrogels and membrane systems. Within the last few years we have finalized several big “evolutionary” projects; we have completely re-designed and commissioned the main components of the instrument: selector area, mirror positioning system, main sample station at 10m, beam-stop system; implemented new sample stations at 3.5 and 1.3m, second (very-high resolution) detector, polarization and polarization analysis systems; adapted the instrument to almost any existing/requested sample environment like 6-position Peltier furnace (-25°C to 140°C), high-temperature furnace (< 1600°C), cryostats/inserts (>20 mK), liquid pressure cell (<5 kBar/10-80°C), CO2/CD4 gas pressure cell (<0.5 kBar/10-80°C), humidity cell/generator (5-95%/10-90°C), magnets (horizontal < 3T, vertical < 2.2T), Bio-logic® multimixer stopped flow (5-80°C), rheometer Anton paar (tangential/radial) etc.

Speaker: Dr Vitaliy Pipich (Jülich Centre for Neutron Science JCNS at Heinz Maier-Leibnitz Zentrum MLZ Forschungszentrum Jülich GmbH)

72 P-84: KWS-X: A Powerfull SAXS/WAXS/USAXS Beamline at JCNS-MLZ

The customized SAXS/WAXS instrument began user operations in April 2023. As the latest addition to our small-angle scattering instrument family, which uses X-rays as the primary probe, the new instrument is equipped with a high-flux Metal-Jet source and a movable Eiger2R 4M SAXS detector. It also features a 4-axis motorized WAXS detector and a Bonse-Hart USAXS system, enabling a broad scattering vector q range from 0.0002 to 7 Å⁻¹. This corresponds to the capability to investigate structures spanning length scales from a few angstroms to micrometers.

Compared to other instruments, it is further enhanced by a spacious sample environment station that operates under ambient pressure conditions. This versatile sample stage supports various in situ platforms commonly used in SANS experiments, such as rheometers, electromagnets, stopped-flow devices, FT-IR spectrometers, and electrochemical workstations. The extensive array of sample environment accessories allows experiments to be conducted over a temperature range of -150°C to 1000°C, under diverse conditions including shear, humidity, tensile deformation, as well as coupled techniques such as SEC-SAXS and Raman-SAXS.

The instrument’s design, combined with its wide selection of sample environments, makes it a powerful tool for investigating nanostructures—including size, shape, formation mechanisms, and particle–particle interactions in solution. It will greatly assist users of our neutron scattering facilities (such as SANS and reflectometers) in acquiring complementary X-ray structural information and will streamline the selection of suitable samples for neutron instruments, thereby improving the efficiency of our neutron scattering user programs, particularly SANS.

Since its opening in 2023, KWS-X has provided more than 8,000 hours of beam time to over 80 users and supported more than 120 proposals. Within a short period, it has already contributed to over 36 high-quality publications in renowned journals including Nature Nanotechnology, Nature Communications, Advanced Materials, JACS, Matter, and Angewandte Chemie.

Speaker: Dr Baohu Wu (JCNS-MLZ, FZ Juelich)

73 P-42: Localized High-Concentration High-Entropy Electrolytes for Superior Lithium Metal Anodes via Solvation Cluster Regulation

The practical application of lithium metal batteries (LMBs) is primarily challenged by the unstable interface between the lithium metal anode (LMA) and conventional electrolytes, leading to dendritic lithium growth and low Coulombic efficiency. While localized high-concentration electrolytes (LHCEs) mitigate these issues by modulating solvation structures, their cluster configurations and interfacial stability require further optimization. This study designs a novel localized high-concentration high-entropy electrolyte (LHCHEE) specifically for LMBs. We systematically investigate the solvation chemistry and reveal that the high-entropy effect fosters the formation of robust, anion-coordinated clusters with enhanced uniformity and stability. This unique solvation structure promotes the preferential decomposition of anions, facilitating the construction of a highly inorganic-rich, robust solid electrolyte interphase (SEI) on the LMA. Consequently, symmetric Li||Li cells with the LHCHEE achieve exceptional cycling stability with ultra-low polarization, while Li||Cu cells demonstrate significantly improved Coulombic efficiency. Furthermore, full cells paired with high-voltage cathodes exhibit remarkable capacity retention. This work underscores the critical role of entropy in engineering solvation clusters and provides a groundbreaking strategy for stabilizing lithium metal anodes.

Speaker: Haixuan Luo (Department of Physics, TUM)

74 P-06: Machine learning based Optimization of Measurement Strategies for Small Angle Neutron Scattering

Small-angle neutron scattering (SANS) is one of the most important techniques for microstructure determination, which is used in a wide range of scientific disciplines such as materials science, physics, chemistry, and biology. Conventional SAS can probe microstructural (density and composition) inhomogeneities in the bulk and on a mesoscopic length scale between a few and a few hundred nanometers.
Despite drastic improvements over the last decades, SANS is inherently flux limited, similar to any other neutron scattering technique, caused by the limited brilliance of todays neutron sources, that is essentially given by the properties of the target or core materials. Consequently, the acquisition of high-quality measurement data necessitates the efficient utilization of available beamtime.
We report on the preliminary findings of a novel methodology designed to enhance the efficiency of small-angle neutron scattering (SANS) experiments.
In this project, we use algorithms based on machine learning to optimize and automatize the measurement strategy of a pinhole SANS instrument, based on a set of exemplary standard SANS samples. Our model includes the desired statistical resolution, intensity and Q-resolution for the different geometrical setting of the instrument. Finally, an attention based neural network for the analysis of isotropic I(Q) data is proposed as a key component within our artificial intelligence (AI)-driven framework for optimizing the measurement strategy.
Therefore our project may form an important contribution to developing a fully autonomous SANS experiment.

Speaker: Gregor Bulitta (Technical University Munich)

75 P-36: MARIA – The high-intensity polarized neutron reflectometer of JCNS

The high-intensity reflectometer MARIA of JCNS is installed in the neutron guide hall of the FRM II reactor in Garching and is using a velocity selector as a primary wavelength filter with a resolution of 10%. The full cross section of the beam is optionally polarized by a double-reflecting super mirror and in the vertical direction the elliptically focusing neutron guide increases the flux at the sample position and consequently reduces the required sample size or measuring time. A flexible Hexapod, as sample table, can be equipped with an electromagnet (up to 1.1T) or a cryomagnet (up to 5T), low temperature sample environment, a UHV-chamber (10−10 mbar range) for the measurement of Oxide MBE samples (transfer forth and back) and last but not least with various soft matter solid/liquid interface cells connected to a “sample robot” for automatic solvent contrast exchange and remote controlled heating/cooling.
Together with the 400 x 400 mm² position sensitive detector and a time-stable ³He polarization spin filter based on Spin-Exchange Optical Pumping (SEOP), the instrument is well equipped for investigating specular reflectivity and off-specular scattering from magnetic layered structures down to the monolayer regime. Furthermore the GISANS option can be used to investigate lateral correlations in the nm range. Due to the large detector even grazing incidence diffraction measurements are possible. All the options, like GISANS, polarization and ³He polarization spin filter can be moved in and out of the beam in seconds by remote controlled push button operation and do not require any realignment.
MARIA is a state of the art reflectometer at a constant flux reactor. It gives the opportunity to investigate easily reflectivity curves in a dynamic range of up to 7-8 orders of magnitude including off-specular scattering and GISANS measurement. We discuss aspects of instrument operation without a cold-source and additionally recent changes and upgrades related to a new relaxed resolution velocity selector and to the installation of additional post-collimation guides for boosting the neutron flux at the sample position.

Speaker: Alexandros Koutsioumpas (JCNS)

76 P-03: MLZ-ELN: A Step Toward Smarter Experiment Documentation

The recent reactor downtime at MLZ was used productively to modernize its digital infrastructure. One of the key upgrades is the introduction of Single Sign-On (SSO), which lets users access all data services using their familiar GhOST credentials—no extra logins needed.
During experiments, NICOS handles live metadata capture, while the MLZ electronic laboratory notebook (MLZ-ELN) takes care of storing the scientific data—everything from instrument settings to sample details and results. The ELN makes this data easy to find, secure, and ready for long-term use.
Together, these tools simplify how data is collected and managed, making it easier for researchers to focus on the science and paving the way for more integrated digital workflows.

Speaker: Josef Baudisch

77 P-08: Modelling backscattered positron capture at the coincidence Doppler broadening spectrometer

The coincidence Doppler broadening spectrometer (CDBS) at the MLZ provides state-of-the-art, depth dependent detection of defects and chemical composition at the annihilation site. A monoenergetic positron micro-beam (50 µm FWHM) is guided onto a sample where positrons may thermalise and annihilate with electrons. The Doppler broadening of the characteristic 511 keV annihilation peak is measured by observing both emitted photons simultaneously.
The measurement quality depends on the size and energy of the beam, both of which are monitored and controlled [1]. However, up to ~ 40% of the incident positrons are backscattered at the sample surface, resulting in a distribution of positrons with a large spread in energy and scattering angle. The annihilation events occurring when these backscattered positrons return to the sample or annihilate in experimental hardware contribute unwanted signal to the measured spectrum which cannot be removed in data processing. We present simulations and hardware design for an upgrade to the CDBS which will allow backscattered positron capture. We use an in-house particle tracking code to design a positron dump that will capture backscattered positrons at a negatively biased electrode and will be shielded from detector lines of sight. This will remove the unwanted signal from the detected spectrum and improve the quality of CDBS data.
[1] Gigl, T. et al. (2017). New Journal of Physics, 19(12), 123007.

Speaker: Leon Chryssos

78 P-79: Multiplexing TAS measurements assisted by active learning

Three-axis spectrometers (TAS) are versatile instruments to study inelastic neutron scattering. They allow high energy resolution investigations of fundamental excitations across various energy and momentum coordinates. However, traditional TAS methods are limited by point-by-point measurement in reciprocal space, which can be time-consuming and less effective for rapid kinetic studies. A promising method to more efficient TAS measurements is the multiplexing technique, such as Multiplexing-PUMA (thermal TAS at MLZ) [1]. This method allows simultaneous measurements across 11 (Q, Ef)-channels, enabling broader reciprocal space mapping.
The ARIANE (ARtificial Intelligence-Assisted Neutron Experiments) approach has proven effective in optimizing single-point TAS measurements [2]. By applying machine learning techniques, it improves data acquisition efficiency. Building on this foundation, we propose an innovative extension of the ARIANE framework for multiplexing measurements at PUMA. This extended approach will employ an active learning algorithm to dynamically identify regions of interest in the (Q,E)-space. It will suggest and measure 11 different locations, provided it complies with the physical constraints of the PUMA multiplexing setup. This will significantly enhance information gain and overall mapping efficiency, maximizing the utilization of neutron beam time for users.

References:
[1] Sobolev et al., Nucl. Instrum. Methods Phys. Res. A. 772, 63-71 (2015)
[2] Parente et al., Nat. Comm. 14, 2246 (2023)

Speaker: Eugenio Vitale (TUM)

79 P-75: NAA - an Instrument for Elemental Analysis

Neutron activation analysis (NAA) is a highly sensitive method of chemical analysis with neutrons. The FRM II provides flux values of up to 10^14 /cm^2s in selected irradiation positions near the reactor core. The high degree of thermalization is optimal for analysis, as corrections due to interfering reactions are usually negligible. The irradiated samples can be transported via a rabbit system from the FRM II to a laboratory in the Radiochemistry Munich (RCM) building, where three counting stations are available. Their electronics (spectrometers) have recently been upgraded so that advanced features, e.g. list mode, can be implemented.

The detection limits are low, in certain cases they even reach the ppq range. The capabilities of the PGAA and NAA instruments complement each other. The advantages and limitations are described in detail on the poster. The NAA instrument is not dependent on status of the cold source.

Speaker: Dr Christian Stieghorst (TUM / FRM II)

80 P-19: Neutron Depth Profiling (NDP) - a versatile tool for studying battery components

Background
Using sophisticated methods, a deep understanding of the processes in in-situ electrochemistry is achieved. There are only a few ways to study electrochemically relevant processes on different length and/or time scales without influencing the processes themselves. What is needed are probes that cover a sufficient volume of the sample non-destructively and are sensitive to the important charge carriers. In battery research, the observation of the near-surface element lithium (Li) is a challenging topic due to the low sensitivity of Li and other light elements with standard probes such as X-rays or electrons.

Methods
Neutrons are an ideal candidate for this task because they are non-destructive and have a relatively high sensitivity to light chemical elements, can distinguish neighboring elements of the periodic table, have a large beam cross section, and have a high penetration depth for many materials. In particular, the neutron depth profile (NDP) is a method for determining the Li depth profile in the first approximately 100 micrometer. Improvements through higher neutron flux, better detectors [1] and sample design [2] even make it possible to measure a complete battery cell operando [2].

Results/Conclusion
This study characterizes a metal-free polymer-based current collector for high-density lithium metal batteries [3]. The Li distribution with NDP of the polyethylene and carbon black mixture on the surface and inside explains with additional methods the advantages of the PE/C collector over the Cu collector through a significant increase in specific energy and significantly lower costs.

References:
[1] R. Neagu, S. Golenev, L. Werner, C. Berner, R. Gilles, Z. Revay, L. Ziegele,J. Plomp, B. Maerkisch, R. Gernhäuser
4D Tomography for neutron depth profiling applications
Nuclear Instruments & Methods in Physics Research A (2024), 1065.

[2] F. Linsenmann, M. Trunk, P. Rapp, L. Werner, R. Gernhäuser, R. Gilles, B. Märkisch,Z. Revay, H.A. Gasteiger, A liquid electrolyte-based lithium-ion battery cell design for operando Neutron Depth Profiling
Journal of the Electrochemical Society (2020), 167, 100554.

[3] M. Wan, R. Gilles, J. Vacik, H. Liu, N.L. Wu, S. Passerini, D. Bresser, Ultralight Polymer Current Collector for High Energy Density Lithium-Metal Batteries, Small (2024), 2404437.

Speaker: Ralph Gilles

81 P-78: Neutron Depth Profiling for Determining Lithium Inventory Losses in Bare and Ag-Coated Cu Current Collectors for Lithium Metal Batteries

Copper is widely used as a current collector in lithium metal batteries due to its electrical conductivity and mechanical stability. However, its inherently low lithiophilicity often results in uneven lithium plating and stripping, which fosters dendrite growth and negatively impacts cell safety, cycle life, and overall performance. To mitigate these issues, surface modifications such as silver (Ag) coatings have been investigated to improve interfacial properties and promote more uniform lithium nucleation.

In this work, we employed Neutron Depth Profiling (NDP), a non-destructive and highly sensitive technique to study lithium distribution within current collector materials [1,2]. NDP provides sub-micrometer depth resolution, enabling the detection of lithium penetration and accumulation beneath the surfaces of both bare and different Ag-coated Cu collectors after electrochemical cycling. Such depth-resolved insights directly reveal irreversible lithium losses to the current collector, offering a clearer understanding of lithium inventory decay mechanisms and supporting strategies for designing more lithiophilic surfaces or protective interlayers in lithium metal batteries [3].

Our findings highlight the effectiveness of NDP in tracking lithium diffusion into the collector bulk and quantifying inactive (dead) lithium formed during cycling. Furthermore, the impact of Ag coating thickness and interfacial characteristics is discussed, underscoring the utility of NDP as a powerful tool for interfacial studies in lithium metal systems and for guiding the development of next-generation batteries with improved durability and performance.

[1] M. Trunk, M. Wetjen, L. Werner, R. Gernhäuser, B. Märkisch, Z. Révay, H.A. Gasteiger, R. Gilles, Mater. Charact., 146, 127-134 (2018)
[2] J. Vacík, J. Červená, V. Hnatowicz, V. Havránek, D. Fink , Acta Phys. Hung. 75 ,369-372 (1994)
[3] M. Wan, R. Gilles, J. Vacik, H. Liu, N. Wu, S. Passerini, D. Bresser, Small, 20, 2404437(2024)

Speaker: Seda Ulusoy (TUM, FRM II)

82 P-72: Neutron Flux Characterization at the FRM II

As one of the world’s leading research reactors, the Munich neutron source FRM II has a rich program in science, industry, and medicine. Modern nuclear security standards motivate intensive efforts to convert FRM II from using Highly Enriched Uranium (HEU) to Low-Enriched Uranium (LEU) fuel. This requires a deep understanding of the reactor behavior to fulfill safety restrictions and allow for experimental characterization in agreement with simulation calculations. To update the existing reactor model, flux monitor data since the first commissioning in 2004 is analyzed. Moreover, the integral and differential neutron flux at the exit of the two neutron guides SR-4a and SR-10 will be measured using time-of-flight spectroscopy and gold-foil activation during the upcoming reactor commissioning in summer 2026. Therefore, an optimized chopper setup is designed to perform precise and absolute flux measurements of the thermal reactor spectrum between 1 and 8 Å. Stand-alone gold-foil activation measurements are planned at additional neutron guides. The experimental results can be used to benchmark today’s simulation studies based on MCNP and McStas. This will allow for validation and optimization of existing reactor models, not only for FRM II, but for nuclear reactors in general.

Speaker: Korbinian Stangler

83 P-38: NICOS

Instrument control software at MLZ

Speaker: Mr Jens Krueger

84 P-04: PANDA – The high flux, cold neutron three-axis spectrometer at MLZ

PANDA is the cold three-axis spectrometer at MLZ, successfully serving scientists from around the world since 2005. In preparation for continued user operations, the instrument has undergone comprehensive maintenance and upgrades. It is now equipped with a new double focusing PG-002 monochromator, a versatile sample table capable of supporting cryomagnets, dilution inserts (50 mK) and a new ADR cryostat operating continuously from room temperature down to 300 mK (and 100 mK in single-shot mode). Translational and rotational degrees of freedom are retained even with the heaviest equipment.

Due to the thermal overlap in the incoming neutron spectrum, PANDA will be ready for experiments immediately upon the restart of user operations. Planned addition of a Cu-111 and a bent Si-111 monochromator aim to extend the energy range or minimize second-order contamination, respectively. Simulations indicate that the incoming flux at the sample position will reach 1.8 × 107 n/cm²/s at ki = 1.9 1/Å. Standard PG-filter experiments for energy transfers up to ΔEmax ≈ 35 meV, as well as high-resolution Be-filter experiments up to ΔEmax ≈ 12-15 meV can be performed, albeit neutron flux is reduced for low energy and high-resolution experiments.

A key aspect of PANDA's restart will be the commissioning of the BAMBUS multiplexing option. Although it is designed for a cold spectrum, immediate tests, background characterization, and software validation are needed to enable its use as soon as possible.

Speaker: Dr Lukas Beddrich (Jülich Centre for Neutron Science (JCNS) at MLZ, Forschungszentrum Jülich GmbH, Garching, Germany)

85 P-58: Performance and Aging Behavior of Multi-tab 26650-type LFP Lithium-ion Batteries

Two commercial LFP|C cells of 26650-type were investigated non-destructively using a combination of electrochemical measurements, X-ray computed tomography (CT), diffraction and differential thermal analysis (DTA) to assess structural uniformity, lithium distribution, and aging behavior.
Despite identical cell chemistry and form factor, significant differences between the two cell types were noticed. Variations in charging profiles were attributed to differences in mobile lithium availability and cell balancing. Both cells employed a multi-tab electrode connection scheme with eight current collectors in total; however, distinct wiring layouts were revealed by X-ray CT, directly affecting lithium distribution and electrochemical performance. Notably, one cell exhibited severe electrode deformation and shorter lifetime, while the other displayed minor housing deformation but longer durability. Cycling data indicated heterogeneous lithium distribution as a critical factor for accelerated aging in the short-lived cell, whereas electrolyte degradation followed similar pathways in both cells, as suggested by DTA results.
The study highlights that external cell geometry does not necessarily reflect internal structural changes, underscoring the need for advanced, spatially resolved, non-destructive diagnostic tools. Beyond the current 26650 format, these insights are directly relevant to the development and evaluation of emerging large-format cylindrical cells (e.g., 4680, 4895), where uniformity and reliability are crucial for safe and efficient electric vehicle integration. Overall, this work emphasizes the role of internal connection schemes, lithium distribution, and mechanical integrity in determining Li-ion battery lifetime, and advocates for realistic cycling protocols in future investigations to better capture automotive-use aging phenomena.

Speaker: Dominik Petz

86 P-07: Perovskite Nanocrystal Nucleation Seeds for Improved Microstructure and Faster Crystallization in Organic-Inorganic Halide Perovskite Thin Films

Organic-inorganic halide perovskites have gained a huge interest in the scientific community owing to their favorable optoelectronic properties combined with their ease of production and abundance of raw materials. In many cases, polycrystalline thin films are fabricated for which thin film crystallinity and morphology are key factors affecting the perovskite properties. In this work, we present a novel approach for improving the thin film quality by employing external perovskite nanocrystals as seeds in slot-die coated formamidinium lead iodide thin films. Grazing incidence wide angle X-ray scattering (GIWAXS) and in-situ optical spectroscopy measurements show that the seed crystals improve the thin film texture by inducing a preferred crystallite orientation. Furthermore, we reveal a new crystallization pathway in seeded thin films with respect to unseeded ones via in-situ GIWAXS measurements.

Speaker: Mr Altantulga Buyan-Arivjikh (Technical University of Munich, TUM School of Natural Sciences, Department of Physics, Chair for Functional Materials)

87 P-11: Phase changes of the 3D printable aluminum alloy A6061 RAM using laser powder bed fusion additive manufacturing

In the last decades alternative production methods for alloys have become the focus of science and industry. One of these production methods is using laser powder bed fusion (LPBF), in which alloys can be printed in complex, delicate and hollow shapes and geometries, which is difficult for the conventional casting and forging approach. The 3D printable alloys are used in the area of transportation and industry.
A cooperation (BMFTR project “AlaAF”) was started between Colibrium Additive, Friedrich-Alexander Universität Erlangen-Nürnberg and Technical University of Munich to improve the printing properties of aluminum alloys with added “reactive additive manufacturing” (RAM) particles. Printing aluminum alloys using the LPBF method led to large, columnar grains in build direction, which in particular for conventional high-strength and forging alloys cause internal residual stress, anisotropic mechanical properties and higher probability of crack formation. To prevent this crystal growth RAM particles are added, which react during the printing process and form ceramic particles inhibiting the growth of the Al grains.
X-ray diffraction (XRD) and neutron diffraction (ND) experiments were conducted on the raw powder and consolidated material after the printing process and heat treatment to follow the phase changes. ND enables the detection of light element phases such as B4C even in real bulk samples (up to cm3), which can’t be observed using XRD due to the low electron count of these elements and the small beam size. Besides phase compositions, diffraction experiments can also be utilized to investigate the microstructure of the materials alongside the crystallite size and crystal structure defects analysis.

Speaker: Dr Stefan Engel (Heinz Maier-Leibnitz Zentrum (MLZ))

88 P-25: Polarized Hot Neutron Diffractometer POLI

We present the hot neutron two-axis diffractometer POLI, which uses spin-polarized neutrons for magnetic studies in particular. We give an overview on the capabilities as well as recent upgrades of the instrument.

Speaker: Leonie Stödter (JCNS at MLZ, Forschungszentrum Jülich GmbH)

89 P-74: Presenting the APEX e+e- pair plasma project at FRM II

Laboratory studies of magnetically confined electron-positron “pair” plasmas are a compelling frontier in fundamental plasma physics research; this is the goal of A Positron Electron eXperiment. The overall project plan involves installing several small plasma devices together at the world-class ­NEPOMUC positron source at FRM II. Positrons will be accumulated and stored in a series of linear, non-neutral plasma traps; these will then feed e+ pulses to either of two table­top-sized, toroidal confinement devices with complementary magnetic topologies. In the levitating dipole APEX-LD (Levitating ­Dipole) and the stellarator EPOS (Electrons and Positrons in an Optimized Stellarator) – both based on HTS coils – the positrons will be combined with electrons and their plasma properties investigated. To date, all of these devices have been developed and operated separately; within coming year, they will start to be installed together in the new e+ experiment space of FRM II's East Hall.

Speaker: E. V. Stenson

90 P-54: PUMA Thermal Neutron Three-Axes Spectrometer at MLZ

Presenting instrument PUMA, thermal-neutron three-axes spectrometer.

Speaker: Jitae Park (MLZ, TUM)

91 P-44: REFSANS: The horizontal time-of-flight reflectometer with GISANS option at the Heinz Maier-Leibnitz Zentrum

REFSANS is the horizontal TOF reflectometer installed at the MLZ, designed for reflectometry and GISANS studies of any interface, as well as to give simultaneous access to a wide range of Qz values.
Wavelength resolution may be tuned from 1.0 % up to 10%. The optics comprises neutron guide elements with different channels and special apertures to provide slit smeared or point focused beams for NR and GISANS measurements, respectively.
The investigation of kinetic processes is possible thanks to the possibility to embrace a large Qz-range with a single instrumental setting. Time resolution can be pushed down to 30 s with data recorded in event-mode: this feature makes possible to perform various time re-binnings in order to tune the resolution/ intensity trade-off after the experiment.
Here we describe the next upgrade of the instrument, which aims to increase its performance and the neutron flux at the sample position, with gain factors ranged between ~ 2 and ~ 8, depending on the optical setup. Furthermore, the instrument performance in the absence of the cold source, as well as potential related applications, are discussed.

Speaker: Gaetano Mangiapia

92 P-71: Relocation and upgrade of the cold triple axis spectrometer FLEXX at MLZ, Munich: Larmor diffraction and inelastic scattering

The cold triple-axis spectrometer (TAS) FLEXX at HZB was a well-designed and upgraded instrument [1-4]. There was a strong wish that this excellent instrument should be preserved for the community. One attractive gap in the present instrumentation suite of MLZ, is the Larmor-diffraction technique [5-6] (LD) and, as a natural extension, cold neutron resonant spin echo (NRSE). TAS comes at no extra cost, as it is the main backbone of such an instrument.
The instrument will be placed on a cold neutron guide and essentially merged with the former MIRA TAS. Further, new developments are under way to allow for application of magnetic fields at the sample, hitherto not possible [7-9]. This opens up new vistas in the exploration of materials. A last attractive option is the possibility to combine high magnetic fields together with cold TAS.

[1] M. Skoulatos et al., NIMA 647, 100 (2011).
[2] M.D. Le et al., Nucl. Instr. Meth. Phys. Res. A 729, 220 (2013).
[3] F. Groitl et al., Rev. Sci. Instrum. 86 025110 (2015).
[4] K. Habicht et al., EPJ Web of Conferences 83, 03007 (2015).
[5] M.T. Rekveldt, Jour. Appl. Phys. 84, 31 (1998).
[6] M.T. Rekveldt et al., Europhys. Lett. 54, 342 (2001).
[7] Neutron Spin Echo - Proceedings of a Laue-Langevin Institut Workshop, Grenoble, Springer- Verlag, Ed: F. Mezei (1980).
[8] M.T Rekveldt et al., Jour. Appl. Cryst. 47, 436 (2014).
[9] K. Habicht, “Neutron-Resonance Spin-Echo Spectroscopy: A High Resolution Look at Dispersive Excitations”, Habilitation, University of Potsdam (2016).

Speaker: Markos Skoulatos (TUM)

93 P-09: Reorientation-Driven Degradation in Oriented Perovskite Films: Shifting Facet Engineering to Thermodynamic Stability

Hybrid perovskite solar cells (PSCs) suffer from underexplored links between crystallographic orientation and thermal stability, especially in narrow-bandgap devices. We fabricate highly oriented mixed Sn-Pb perovskite films via an additive-free two-step method. Accelerated ageing studies at 120 °C reveal that high orientation paradoxically compromises stability, and PSCs built from highly oriented perovskite films retain only 73% of their initial PCE versus 89% in less-oriented devices. Operando grazing incidence wide-angle X-ray scattering of the PSCs shows that thermal stress induces significant reorientation and lattice distortion in the oriented crystallites, accumulating pronounced microstrain that accelerates the PSC degradation. Structural analyses confirm progressive crystallographic transitions, including grain reconfiguration, shifts toward isotropy, and systematic diffraction migrations. Critically, we demonstrate that metastability is an intrinsic consequence of high crystallographic order, which is why the very high alignment strategies that enhance performance induce thermodynamic vulnerability. This necessitates redesigning crystal engineering priorities where suppressing instability requires engineering thermodynamic equilibrium states over maximising alignment for stable perovskite photovoltaics.

Speaker: Xiaojing Ci

94 P-24: Revealing the structure formation of biohybrid films with machine learning-assisted scattering methods

The development of biohybrid materials promises an advancing sustainable nanotechnology, for example, in the synthesis of functional inorganic nanostructures for photocatalysis. This work presents a water-based route using the bovine whey protein ß-lactoglobulin (ß-lg) as a biotemplate for fabricating nanostructured and crystalline titania films. To reveal the complex formation mechanisms of these organic-inorganic systems, we employe a set of grazing-incidence scattering techniques. Grazing-incidence small-angle neutron scattering (GISANS) is particularly valuable, providing essential contrast to complement X-ray small- and wide-angle scattering (GISAXS/GIWAXS) data in resolving the evolving hierarchical structure. Time-resolved scattering experiments following the fast kinetic processes of biohybrid film formation generate complex datasets representing a challenging inverse problem, where deriving structural models from the scattering signals is non-trivial. To overcome this analytical bottleneck, we use machine-learning supported analysis for the quantitative interpretation of the scattering data, enabling the real-time extraction of domain sizes and accelerating the optimization of green synthesis pathways for tailored photocatalytic materials.

Speaker: Julian Heger

95 P-65: RIANA - Research Infrastructure Access in NAnoscience & nanotechnology

RIANA is a Horizon Europe project offering free, transnational access to 69 leading research facilities across 22 countries. Through cutting-edge techniques, including electron microscopy, synchrotron radiation, and nanofabrication, RIANA supports breakthrough research in nanoscience and technology. A unique feature is its dedicated network of Junior Scientists, who provide expert, one-on-one support throughout the user journey. With rolling open call and a strong focus on interdisciplinary collaboration, RIANA accelerates innovation and empowers researchers to tackle major scientific challenges.
As part of the LENS network, Juelich Centre for Neutron Science contributes to RIANA by offering access to six instruments and expert scientific support. Available techniques include Small-Angle Neutron Scattering (KWS-1 and KWS-2), Neutron Reflectometry (MARIA), and Neutron Diffraction (HEIDI, POLI, and BIODIFF).

Speaker: Debasish Saha (FZ Juelich)

96 P-05: Role of Solvation Shell Composition in Polysaccharide Conformational Bistability

Polysaccharides are crucial structural polymers of life and display a diverse set of conformations, although the origins of these conformations are not fully understood. In this study, a high molecular weight pectin polysaccharide was investigated in binary water–glycerol mixtures using a complementary combination of molecular dynamics simulations, rheology, calorimetry, and neutron scattering. By systematically varying solvent quality, the polymer chain was observed to undergo a non-monotonic sequence of conformational transitions: flexible → extended → collapsed, accompanied by pronounced shifts in viscoelastic response. Simulations revealed molecularly adsorbed water accumulating within ca. 0.40 nm of the chain surface as the glycerol fraction increased, indicating water’s preferential association with the polymer. Elastic fixed window scans on IN13 (ILL, France) and quasi-elastic neutron scattering on IRIS (ISIS, UK) substantiated this observation. The emergence of such preferential solvation is proposed to result in a dynamically heterogeneous solvation state that is entropically unfavourable, thereby promoting compensatory swelling and collapse of the polysaccharide chain. Results connect solvation-shell composition to conformational bistability and rheological behaviour, offering fundamental insights of broad relevance to soft matter, food physics, and the rational design of adaptive biomaterials.

Speaker: Dr Pallab Kumar Borah (Technical University of Munich)

97 P-82: Sample Environment activities for the MLZ user operation relaunch

In this poster you will have the opportunity to see the tasks we have carried out for the MLZ user operation relaunch.

Speakers: Dr Alexander Weber (Forschungszentrum Jülich GmbH), Dr Manuel Suarez Anzorena (Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München (TUM))

98 P-49: SANS-1 Small-angle neutron scattering for materials research and strongly correlated electron systems

SANS-1 is a joint project of the TU München and the Helmholtz-Zentrum Hereon exploiting a classical pin-hole layout. Beside of being a general-purpose instrument it features distinguished characteristics for probing strongly correlated electron systems and materials science research. SANS‑1 offers access to a large dynamic range with tuneable resolution including full polarization analysis. A chopper based TISANE setup allows for μs time resolution for kinetic experiments. For in-situ and in-operando experiments under extreme conditions, SANS-1 features a flexible, spacious sample area with a heavy-duty goniometer hosting almost any complex sample environment like a set of superconducting magnets, furnaces and a bespoke quenching dilatometer. With the SANS-1MAX proposal, we plan to further extend the dynamical Q-range, and to increase the maximal momentum transfer to achieve a unique overlap to the diffraction/wide-angle neutron scattering regime. The upgrade will enable access to new research fields, particularly for modern materials science applications on energy materials.

Speaker: Sebastian Muehlbauer

99 P-80: SAPHiR: Neutron Diffraction and Radiography at extreme Pressure and Temperature

The poster will describe the instrument SAPHiR and give scientific examples.

Speaker: Nicolas Walte

100 P-48: Scanning Positron Microscope (SPM)

Positron annihilation lifetime spectroscopy (PALS) is a powerful tool in a
wide range of materials science. To investigate inhomogeneous defect
distributions, e.g. close to fatigue cracks or in a dispersive alloy, with
PALS a pulsed positron beam with a diameter in the range of 1 µm and a
time resolution in the order of 200 ps is needed.

Speaker: Johannes Mitteneder (Universität der Bundeswehr)

101 P-68: Search for the Fierz Interference Term with PERKEO III

Observables of neutron decay are, among others, the $\beta$-asymmetry $A$ and the Fierz interference term $b$. Through precision measurements of $A$ we have access to the CKM matrix element $V_{ud}$ , while a non-zero Fierz term $b$ would imply the existence of scalar or tensor interactions beyond the V-A theory of the Standard Model.

The currently most precise direct determinations of $A$ and $b$ from $\beta$-spectrum measurements were obtained with the PERKEO III experiment at the ILL PF1b facility. These results are based on the 2009 measurement campaign, using a combined fit to the experimental $\beta$-asymmetry. To control major systematic effects, we used a pulsed beam of cold neutrons. This beam is guided into the 2 m long decay volume of the experiment, in which some of the neutrons decay. The charged particles from the decay follow the magnetic field toward one of two scintillation detectors with PMT readout. 

A subsequent measurement campaign in 2019/20 aimed to measure the electron spectrum from unpolarized neutrons to extract an improved limit for the Fierz interference term $b$. This method offers higher statistical sensitivity but is systematically challenging. We present experimental details as well as the status of the ongoing analysis. Our current focus lies on characterizing the readout electronics and incorporating a comprehensive model of secondary particles induced by our calibration device into the analysis chain.

Speaker: Anna Schubert (TUM ENE)

102 P-91: Self-assembled Micelles from Charged Block Copolymers: Insights from Small Angle X-ray Scattering (SAXS)

Block copolymer micelles have been widely studied due to their flexible structure adaptation and their ability to load drugs. Recently, micelles with a positively charged shell have been proposed to complex DNA, enabling efficient gene therapy. To achieve highly tunable morphologies and multi-biological functions, self-assembled micelles from the diblock copolymers PDMAEMA-b-PLMA and the triblock terpolymers PDMAEMA-b-PLMA-b-POEGMA are investigated in aqueous solution. Here PDMAEMA stands for the weak polycation poly(2-(dimethylamino)ethyl methacrylate), which, in the uncharged state, is thermoresponsive, PLMA for the hydrophobic, but soft poly(lauryl methacrylate) and POEGMA for the hydrophilic poly(oligo(ethylene glycol) methacrylate). The micellar structures are characterized in dependence on temperature at different pH-values using synchrotron small angle X-ray scattering (SAXS). For PDMAEMA-b-PLMA; ellipsoidal core-shell micelles were obtained for all temperatures and pH-values studied, however, the shell thickness and aspect ratio vary. The micelles from PDMAEMA-b-PLMA-b-POEGMA proved pH-dependences as well. Especially when both PDMAEMA and POEGMA shell blocks are short and have similar lengths, strong temperature dependencies of the micellar structures are observed at all pH-values, which indicates a highly flexible control of morphological changes.

Speaker: Yijun Zhao (Technical University of Munich)

103 P-40: Silicon detector for neutron beta decay measurements with PERC

The PERC facility is under construction at the FRM II in Garching, Germany. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to improve the measurements of weak interaction properties by one order of magnitude and to search for new physics via new effective couplings.
PERC's central component is a 12 m long superconducting magnet system. It hosts an 8 m long decay region in a uniform field. An additional high-field region selects the phase space of electrons and protons, which can reach the downstream detector to minimize systematic uncertainties.
The downstream detector and the two upstream backscattering detectors will initially be scintillation detectors with (silicon) photomultiplier readout. A pixelated silicon PIN-detector will replace the downstream detector in a later upgrade. This new detector is 2mm thick. The entrance window consists of a 100nm thin p+ doped layer with a 300nm thin aluminium grid on top, and the readout side is 500nm of pixelated n+ doping.
We are presenting the results of its characterization.

Speaker: Manuel Lebert (Technical University Munich)

104 P-52: Sponge Phase Lipid Nanoparticles for Biomolecular Delivery - Biomimic membrane interact revealed by neutron reflectometry and contrast matching

Lipid sponge phase nanoparticles (L₃NPs) are emerging as versatile carriers for biomolecular delivery due to their curved flexible bilayer structures and interconnected aqueous channels. These bicontinuous nanostructures enable efficient encapsulation of large, sensitive biomolecules, including proteins. However, scalable production
methods and mechanistic insights into their membrane interactions remain underexplored. We use a microfluidic approach to fabricate L₃NPs with and without the heme protein myoglobin (Mb), and investigate their structural features and interfacial behavior with model lipid membranes using a combination of scattering, microscopy, and surface-sensitive techniques. By using neutron reflectometry and different isotopic contrast, H2O and D2O buffers, and deuterated lipids, we can separate between the different components, i.e. lipids and protein. Both lipids and protein (myoglobin) and lipids enter the model biomembrane, consisting of POPC. We show that the integrity of the model membrane is maintained and only lipid exchange occurs with protein free L₃NPs.

Speaker: Tommy Nylander (Lund University)

105 P-43: Status of the neutron decay experiment PERC

The decay of free neutrons is a powerful tool for precision tests of the Standard Model of particle physics. Correlation coefficients - such as the beta asymmetry $A$ and the Fierz interference term $b$ - serve as input for the determination of the CKM matrix element $V_{\mathrm{ud}}$ and for searches for (effective) scalar and tensor as well as right-handed couplings.
The neutron decay spectrometer PERC (Proton Electron Radiation Channel), which is set up at the MEPHISTO beamline of the FRM II, aims to improve the accuracy of several correlation coefficients by up to one order of magnitude. PERC consists of a 12 m long superconducting magnet system, in which the neutron beam is contained by a non-depolarizing neutron guide. The magnetic field guides electrons and protons produced in the neutron decay towards the main detector, which will initially be a scintillation detector with photomultiplier tube readout. A second detector system, which consists of a scintillator read out by silicon photomultipliers, is installed in the upstream area of PERC and allows to identify backscatter events.
The poster gives an overview of PERC and presents the current status.

Speaker: Lilli Löbell (TUM)

106 P-28: STRESS-SPEC – Upgrades and new measurement possibilities

STRESS-SPEC is designed as a state-of-the-art multi-purpose diffractometer for strain and texture analysis at FRM II. Besides the optimized high neutron flux the available large variability in gauge volume definition systems together with the robotic sample handling option offer high flexibility for spatial resolved diffraction measurements.
Recent developments focused on the enhancement of the STRESS-SPEC robotic system with an optical metrology setup that actively tracks and corrects the sample position with a spatial accuracy of better than 50 μm. Furthermore, the incoming slit system was upgraded using a heavy-duty hexapod positioner allowing precise alignment of the gauge volume with respect to the neutron beam axis and the sample center. Finally, we extended the sample environment suite of STRESS-SPEC with a new type of laser furnace and a light-weight tensile rig, both of which can be used with the robot. All these options will be available for the restart of the reactor in 2026.

Speaker: Michael Hofmann

107 P-13: Structural evolution during annealing in rare earth-lithium-chlorides superionic conductors

Ternary lithium lanthanide chlorides, Li₃RCl₆ (R = rare earth), have recently emerged as promising solid electrolytes. Historically, compounds of the Li₃MCl₆ family (M = Sc, In, Ho, Er, Y, Yb, etc.) were regarded as poor ionic conductors, typically showing conductivities several orders of magnitude below relevant values. Recent advances in mechanochemical synthesis have changed this view, as as-milled powders now reach conductivities up to 10⁻³ S cm⁻¹, exemplified by Li₃HoCl₆. These findings have renewed interest in the structural origins of ionic transport in this class of halide conductors. At ambient conditions, the crystal structure follows a systematic size dependence: heavier rare earths such as Y and Tb–Tm stabilize a trigonal close-packed chloride lattice (P-3m1), whereas smaller cations like Yb and Lu adopt an orthorhombic Pnma arrangement. Yet most structural studies have focused on annealed samples, which exhibit lower conductivities. Our measurements confirm that annealing reduces ionic conductivity by about one order of magnitude compared with as-milled powders, underscoring the critical role of microstructural disorder in fast lithium transport. In situ X-ray diffraction shows that annealing drives complex temperature-dependent transformations across the series. Li₃TmCl₆ undergoes a direct trigonal-to-orthorhombic transition between 500 and 550 K. Li₃TbCl₆ follows a sequential pathway, stabilizing in the trigonal phase below 450 K, converting to a triclinic phase from 450 to 600 K, and then transforming into the orthorhombic Pnma structure up to 670 K, before reverting to the trigonal P-3m1 lattice at higher temperature. Li₃DyCl₆ displays an orthorhombic window between 500 and 630 K, with the trigonal modification favored outside this range. In contrast, Li₃HoCl₆ remains predominantly trigonal, with only a brief orthorhombic appearance near 500 K. Kinetic studies at fixed temperature reveal that substantial microstructural reorganization precedes the phase transformation, occurring with remarkably fast kinetics even at relatively low annealing temperatures. The conductivity loss upon annealing is therefore closely linked to structural and microstructural relaxation. By correlating conductivity with symmetry evolution and thermal history, this work highlights the central role of processing conditions in enabling or suppressing high ionic conductivity and offers insight into the design of high-performance solid electrolytes.

Speaker: Francesco Falsina

108 P-90: Structure and transport properties of Li–Zr–Cl–O oxychloride solid electrolytes

Modern society permanently requires more advanced, better performing, and safer energy storage devices. All-solid-state batteries employing halide-based electrolytes have attracted attention due to their promising combination of room-temperature ionic transport, formability, and interfacial compatibility. Within this class, oxychloride compositions offer an additional degree of freedom via anion chemistry while retaining the beneficial processing of chlorides.
The current study deals with the systematic characterization of mechanochemically prepared Li–Zr–Cl–O oxychlorides produced exclusively by high-energy ball milling. A targeted Li2+yZrCl6-yOy series was established under standardized processing conditions, followed by pellet preparation with fixed thickness and stack pressure to ensure comparability. Laboratory powder X-ray diffraction (phase identification and Rietveld analysis of lattice parameters and microstrain) was employed to quantify the structural response to changing oxygen content and processing conditions. Electrochemical impedance spectroscopy yielded ionic conductivities and activation energies at ambient temperature. The resulting dataset provides a detailed composition–processing–structure–transport map for Li–Zr–Cl–O and delineates a practical recipe window for maximizing room-temperature conductivity under a purely mechanochemical synthesis route, thereby laying a robust laboratory baseline for subsequent interfacial and operando investigations.

Speaker: Mr Ziyan Zhang (TUM)

109 P-56: The Data Evaluation Group

Data Evaluation Group (DEVA) offers support for processing and evaluation of experimental data collected at selected neutron and x-ray instruments of the MLZ. Our service is particularly focused to support infrequent or new users to facilitate data analysis to obtain meaningful results ready for publication in short time. This includes assistance in data reduction, data analysis steps with use of common software tools as well as guidance in interpretation and manuscript writing.

Our group holds regular method-based educational workshops with support of instrument scientists and software providers, each workshop offering insights into a different neutron technique and the related software needed for data analysis. With this concept, multiple goals are achieved, such as training new generation of neutron scientists, encouraging interdisciplinary partnerships between experienced scientists, and interactive sessions with software providers to obtain users’ feedback for further software development.

Here, we provide an overview of the group's capabilities, summarize its recent activities, and present an outline of future developments.

Speaker: Dr Neelima Paul (Technical University of Munich, Heinz Maier-Leibnitz Zentrum (MLZ))

110 P-88: The high resolution neutron backscattering spectrometer SPHERES

SPHERES (SPectrometer for High Energy RESolution) is a third-generation backscattering spectrometer with focusing optics and a phase-space-transform chopper. It combines the high energy resolution with a very good signal-to-noise ratio. It is a versatile spectrometer for investigating atomic and molecular dynamics on a μeV scale. Typical applications include for example hyperfine splitting or rotational tunneling, molecular reorientations, diffusion and relaxation processes in various systems.

Speaker: Michaela Zamponi (Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at Heinz Maier-Leibnitz Zentrum)

111 P-62: The JCNS KWS-2 diffractometer for soft matter and biophysics: SANS/WANS/USANS at the same neutron scattering beamline

KWS-2 is a pinhole SANS diffractometer optimized for the investigation of complex morphologies and rapid structural changes in soft-matter and biophysical systems. The instrument enables the exploration of a broad Q range between 1.0x10$^-$$^4$ and 2.0 Å$^-$$^1$ offering high neutron intensities and adjustable experimental resolution in continuous or TOF mode based on the instrument's optimized neutron guide system, versatile velocity selector, and main double-disk chopper. The wide Q range is covered by the combination of pinhole mode using the main $^3$He tubes MHz detector with the high-resolution (low Q) focusing mode using MgF$_2$ lenses and a secondary HRD (scintillation), and the wide-angle detection mode using an additional WANS-$^3$He tube detectors that collect neutrons scattered up to a scattering angle $\theta$$_s$ = 53° to bridge the atomic and mesoscale at the instrument. A dedicated suite of sample environments is available, with the novelties represented by the in-beam purification of biological samples (SEC) and the controlled hydration (versatile contrast variation SANS-dedicated dew point generator and humidity chamber). In-situ light absorption complementarities are also available for simultaneous analysis of the sample with SANS.

According to the McStas simulations, the flux decrease if only the thermal neutron source (TNS) is available at the FRM II reactor can be mitigated for $\lambda$ ≥ 4.5 Å by using a low-resolution velocity selector that provides a wavelength resolution of 20 % for standard positioning and 35 % when tilted at an angle $\theta$$_i$ = -10° to the beam axis. Based on measurements, this decrease in resolution with increasing intensity appears to be not critical for the structural characterization of small biological morphologies, which would be one of the most studied topics if only thermal neutrons were available at FRM II. Furthermore, by using MgF$_2$ focusing lenses when working with large samples, an intensity gain on the sample of up to 12-fold is achieved while maintaining Q$_{min}$ resolution as with the standard pinhole mode, restoring the flux loss expected with thermal neutrons for $\lambda$ ≥ 7 Å. Wavelengths around 3 Å, which are available at KWS-2 with an inclined velocity selector, are not subject to a significant decrease in flux, so measurements in the high Q regime at KWS-2 are less affected when the CNS is missing (A. Radulescu et al., $\it{J.Appl.Cryst.}$, in press 2025).

Speaker: Aurel Radulescu (Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science at MLZ)

112 P-53: The Macromolecular Neutron Single Crystal Diffractometer BIODIFF at the Heinz Maier-Leibnitz Zentrum

The neutron single crystal diffractometer BIODIFF, a joint project of the Forschungszentrum Jülich and the FRM II, is dedicated to the structure determination of enzymes. Typical scientific questions address the determination of protonation states of amino acid side chains in the active center, the orientation of individual water molecules essential for the catalytic mechanism and the characterization of the hydrogen bonding network between the enzyme active center and an inhibitor or substrate. BIODIFF is designed as a monochromatic diffractometer and is able to operate in the wavelength range of 2.0 Å to about 5.6 Å. This allows to adapt the wavelength to the size of the unit cell of the sample crystal. Without the cold source in place, BIODIFF can operate in the wavelength range of 2.0 Å – 2.7 Å with tolerable losses. The loss at 2.7 Å is approximately 50% compared to operation with the cold source. Recently, the former manual adjustable collimator positioning unit was replaced by a hexapod. This now allows for quick and automated adjustment of the collimation unit. Switching between different aperture setups is now easy via an exchangeable cassette insert. In addition, a new upgraded cryo-insert was installed. The new precise 1-circle goniometer in combination with a x,y,z-stage and mini-kappa-goniometer allows for efficient data collection in combination with the N2-cryo-stream. The new goniometer makes it possible to go beyond the so-called step-scan measurements and to move the omega-axis pseudo-continuously (micro-stepping mode) while the shutter is open. In addition, a potential detector upgrade for BIODIFF will be presented, which will expand the maximum unit cell limits.

Speaker: Andreas Ostermann (Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München)

113 P-29: The Neutron Spin Echo Spectrometer J-NSE “PHOENIX”

The Neutron Spin Echo Spectrometer (J-NSE) 'PHOENIX' enables the study of slow dynamic processes such as the fluctuations of biological membranes and the internal domain motions of proteins. With its superconducting main precession coils and optimised field shape, it is one of the most advanced NSE instruments available. Recent developments to the instrument include the installation of a robotic system for changing samples and apertures. Scientific results published recently will be presented. The prospects for experiments at the J-NSE 'PHOENIX' after the restart will be discussed.

Speaker: Olaf Holderer (Forschungszentrum Jülich GmbH, JCNS at MLZ)

114 P-33: The TIGER Upgrade of the resonant spin-echo spectrometer RESEDA

Presenting RESEDA our neutron resonant spin-echo spectrometer

Speaker: Johanna Jochum

115 P-61: Thin film sample preparation with MBE for neutron reflectometry

Presenting thin film sample preparation with MBE (Molecular Beam Epitaxy) for neutron reflectometry and thin film characterization techniques in the thin film lab.

Speaker: Dr Sabine Puetter (Jülich Centre for Neutron Science JCNS at MLZ, Forschungszentrum Jülich GmbH)

116 P-87: Tiny Intrinsically Microporous Polymer Additives Enhanced Silicon-Based Lithium-Ion Batteries

Silicon-carbon (Si/C) composite anodes are promising candidates for high-energy-density lithium-ion batteries due to the high theoretical capacity of silicon. However, their practical application is hindered by severe volume expansion and unstable solid electrolyte interphase (SEI) formation during cycling. Fluoroethylene carbonate (FEC) is commonly used to improve interfacial stability, but its effectiveness is limited by concentration sensitivity and uncontrollable side reactions. In this study, a carboxyl-functionalized polymer of intrinsic microporosity (PIM-COOH) is introduced as an electrode additive to address these challenges. The intrinsic microporous structure of PIM-COOH facilitates lithium-ion transport, while its chemical functionality promotes the preferential reduction of FEC, leading to the formation of a stable, lithium fluoride (LiF)-rich SEI layer. This dual effect significantly enhances the cycling stability and electrochemical performance of Si/C anodes. Only 0.1% PIM-COOH is required to achieve these effects. Notably, the Si/C@PIM||Li half-cell retains 90% of its capacity after 300 cycles at 1.0 C, demonstrating excellent long-term stability. Furthermore, when paired with a 4.5 V LCO cathode, the PIM-COOH-modified anode exhibits improved interfacial compatibility and high-voltage stability. In situ grazing incidence wide angle X-ray scattering (GIWAXS) and atomic force microscopy (AFM) analyses confirmed that the microporous framework of PIM-COOH remains preserved within the polyacrylic acid (PAA) binder matrix, supporting enhanced lithium-ion transport kinetics. These results demonstrate a scalable and effective strategy for stabilizing silicon-based anodes, offering valuable insight into the design of next-generation lithium-ion batteries with both high energy density and long cycle life.

Speaker: Ming Yang (Technische Universität München)

117 P-83: TOFTOF

Presenting instrument TOFTOF, a cold neutron time-of-flight spectromenter

Speaker: Marcell Wolf (TUM)

118 P-73: TOPAS

Presenting TOPAS, a thermal neutron time-of-flight spectrometer with polarization analysis.

Speaker: Michal Stekiel (Juelich Centre for Neutron Science)

119 P-34: TRISP construction and upgrade

TRISP is currently being set up in the guide hall east. At the same time, the new 30-meter-long neutron guide with transmission polarizer is being installed. Transmission losses of this longer guide are minimized in the thermal spectrum range (1-4 Å) by a ballistic guide with parabolic and elliptic sections at the input and output, each 13 m long. In the center there is a straight transmission polarizer (4 m length), which shows very good performance due to the low beam divergence at the exit of the first parabolic section. This guide design will provide a similar flux at TRISP as before, even with a slight increase at λ < 2 Å. New, optimized spin-echo radio-frequency coils will allow us to double the frequency, thereby improving the energy resolution by a factor of two.

Speaker: Thomas Keller

120 P-21: Upgrades at NREX, the neutron and x-ray reflectometer

We are going to present the upgrades developed at NREX during the shutdown time. We installed new sample environment to investigate thin film samples in H2 or D2 atmospheres: A gas handling system with remote pressure control (0-1bar), a sample chamber with both neutron and x-ray windows, and a He3 cryostat (0.5 - 300K) also with neutron and x-ray windows for simultaneous reflectometry measurements. The cryostat fits into the NREX sample electromagnet (0.5T). We developed new sample holders with spring loaded electrical contacts, which permit simultaneous neutron and x-ray reflectometry. These contacts also work at low temperatures without the need to wire-bond the samples. The contact arrangement is of van-der-Pauw type (4 contacts on a square) connected to a relais matrix, such that the current flow and voltage measurement can be freely assigned, either parallel or perpendicular to the external H field, or in crossed geometry for Hall measurements. The voltage is measured by a sensitive lock-in amplifier, and thus very low excitation currents avoiding sample heating are possible.

Speaker: Laura Guasco

121 P-37: Water dynamics in conductive PEDOT:PSS/cellulose nanocomposite films in dependence of relative humidity and temperature

PEDOT:PSS is a water-dispersable and electrically conductive polymer blend that is increasingly applied as organic electronics in numerous fields such as batteries, super-capacitors, and solar cells. While many studies focus on performance optimization, long-term degradation issues because of humid environments are rarely discussed. PEDOT:PSS absorbs significant amounts of water (~50 wt%), which leads to a pronounced swelling factor of up to 1.6.

The integration of PEDOT:PSS into a cellulose nanofibrils (CNFs) matrix solves this challenge as it enhances significantly the mechanical integrity and limits water absorption. Furthermore, a complex nanocomposite morphology is generated, which changes in dependence on the ambient relative humidity: high humidity leads to de-wetting of PEDOT:PSS from CNF bundles and the formation of larger PEDOT:PSS clusters. As a result, the conductivity decreases. Generally, upon drying, this behavior is reversible, however only after a first drying/humidifying cycle.

By investigating the water dynamics via quasi-elastic neutron scattering, (QENS), we identified two water species inside the films: fast-moving bulk water and slow-moving hydration water. In dry conditions, bulk water is completely released from the films, while parts of the hydration water remain inside the films. The remaining hydration water fraction provides a certain mobility for the PEDOT:PSS chains and supports their wetting on the CNF bundles. Upon temperature increase, we see an increase in hydration water fraction, whereas the bulk water fraction remains constant. In addition, the diffusion, which can be described with the isotropic jump diffusion model) of both water species accelerates, however due to a different reason: while hydration water features similar jump lengths and shorter residency times at elevated temperatures, bulk water moves in larger jumps, but with similar residency times. Raman measurements complement the data obtained from QENS and provide information about the polymer specific hydration and temperature behavior. In combination with conductivity measurements, we establish a link between fundamental water – polymer interactions on the molecular scale to a certain functionality on the macroscopic scale. This will contribute to develop novel types of organic electronic applications with enhanced performance and durability.

Speaker: Dr Lucas Kreuzer (MLZ (FRM II, TUM))