Neutron and X-ray scattering experiments provide valuable insights into the nanoscopic properties of matter, a scale that is also accessible through Molecular Dynamics (MD) simulations. If the simulations reproduce the experiments, they can give greater insight into the material properties on the nanoscopic scale than traditional data analysis methods.
However, existing MD forcefields are...
$A_2B_2O_7$ oxides gathered considerable attention due to many complex and exotic (ground) states observed or theoretically predicted, e.g., spin liquid, spin ice, topological insulator or Weyl semimetal [1,2]. Geometrical frustration of magnetic moments, responsible for these states, is defined very well in $A_2Ir_2O_7$ iridates (with A being the rare earth) since they crystallize in the...
As silicon/graphite (SiG) composites are more commonly used as the anode active material in commercial Li-ion batteries,1 the importance of investigations of the (de-)lithiation behavior of the blended anodes grows. In this study, the charge redistribution between graphite and silicon was investigated in graphite-NMC 622 and SiG (~20 wt.-% Si) – NMC 622 bilayer pouch cells using in situ and...
A persistent challenge for the inelastic neutron scattering technique has been the low scattering cross-section of neutrons, necessitating large sample sizes compared to other techniques. Focusing the neutron beam is a viable technique to increase the flux reaching the sample, but previous techniques suffer from limitations to beam size and quality or an excessively close distance to the...
Neutron supermirrors are multilayer structures of varying bilayer thickness with the purpose of extending the critical angle of the coating, increasing the neutron flux reaching the neutron instruments. The sputtered layers of the supermirrors are mostly made of nickel and titanium due to their excellent scattering contrast. Depolarization effects due to the ferromagnetism of nickel are...
The prediction of material behavior following non-proportional load paths is still a major challenge in forming technology. In-situ synchrotron experiments are used to investigate the material behavior of a microalloyed and a dual-phase steel after different pre-strain levels and directional changes. It is shown that the material behavior is strongly dependent on the pre-forming level and the...
Recent developments in event driven camera systems allow the construction of a new type of scintillator-based event mode imaging devices. This type of detector records data for individual neutron interactions in a scintillator screen. By analyzing each event individually, improvements in temporal and spatial resolution as well as noise supression are possible. At the same time, it has the same...
Quantum materials have been playing a crucial role in the development of next-generation technologies and devices, including quantum computers. Such materials are usually prepared under laboratory conditions. However, some naturally occurring minerals have also been found to feature complex magnetic ground states, such as Henmilite [1] or Herbertsmithite [5,6]. They possess spin ½ Cu ions,...
The mission of the APEX-LD (A Positron-Electron eXperiment - Levitated Dipole) trap is to provide a compact (~10-liter) volume of closed dipole magnetic field lines, to be used for the confinement and study of low-temperature, long-lived e+e- pair plasmas. The requirements for this application posed a number of challenges for experiment design and engineering. (These included, e.g., the need...
High-precision measurements of angular correlations in free neutron beta-decay address a number of questions which are at the forefront of particle physics. PERC (Proton Electron Radiation Channel) is the new generation beta-decay experiment. Its aim is to measure correlation coefficients with high accuracy (10-4) and the experiment is currently under construction at the TUM FRM II/MLZ.
In...
Ferromagnetic metals are commonly used as high performance magnetic core materials. Especially for application in transformers, grain oriented (GO) silicon steels stand out due to their uniaxial magnetic properties, which are founded in their strongly textured crystal structure. Since most techniques for investigating magnetic properties integrate over large sample volumes (magnetization and...
The analysis workflow of Prompt gamma activation analysis at the BNC’s PGAA and NIPS-NORMA facilities, at the MLZ FRM II PGAA station, and many other centers worldwide relied on the use of the Hypermet-PC gamma spectrometry software and the ProSpeRo concentration calculation Excel macro. This evaluation procedure was established in the late nineties and was compatible with the computing...
With increasing share of energy generation from renewables, intermittent electrical energy storage is gaining significance. Sodium-ion batteries (SIB) are currently developed and commercialized as cost-effective complementary technology to today’s Lithium-ion batteries (LIB). For SIBs, P2-type layered oxides are considered amongst the most attractive cathode active materials.
In this work,...
Thermogels are an exciting class of stimuli-responsive materials with many promising applications ranging from the medical field to additive manufacturing. The mechanical properties in the gel state strongly depend on the architecture of the polymer [1].
Here we address an ABC triblock terpolymer and a BABC tetrablock terpolymer consisting of the hydrophilic oligo(ethylene glycol) methyl...
Waterborne latex films, obtained from the dispersion of latex particles are of particular interest due to the non-content of volatile organic compounds (VOC), often mandatory under environmental legislation [1]. However, abrupt water penetration inside the films restricting their lifespan and deteriorating the shining of the coating. In order to prepare efficient and solvent-free coatings with...
The La1-xPrxCrO3 compounds with x = 0.8, 0.85, and 0.87 exhibit the intriguing negative magnetization (NM) state below the compensation temperature, TCOMP. While only positive magnetization is found for x = 0.9 compound below its magnetic ordering temperature. An anomalous dc magnetization behavior is observed for these compounds. A maximum dc magnetization is found for x = 0.8 compound, after...
Ionic assembly of oppositely charged polyelectrolytes with each other or surfactants is a highly versatile way for constructing complexly structured colloidal systems in aqueous solution. Due to the richness of available polyelectrolytes and surfactants one can create here a multitude of structures dissolved in aqueous solution. Such complexes are interesting systems for selective...
Pyrochlore antiferromagnets (AFM) Gd2T2O7 (T: tetravalent metal elements) are prototypical materials for realizing classical spin liquid states. However, all of them have been observed to show long-range magnetic order [1-3]. Previous specific heat data of Gd2Hf2O7 show a tiny sharp peak on the top of a large broad maximum indicating a long-range AFM order [4]. However, our sample does not...
The gradual ferromagnetic spin reorientation in the hcp phase of cobalt between 230 °C and 330 °C reported for a Co single crystal [1] suggests that this phase cannot have a hexagonal symmetry [2,3]. This hypothesis is verified positively by synchrotron radiation diffraction (MSPD@ALBA) and neutron diffraction (SPODI@MLZ and D2B@ILL) on the powder of cobalt [3]. The analysis of diffraction...
We present neutron scattering data on the hexagonal rare-earth diboride ErB$_2$. ErB$_2$ orders magnetically below T$_c$ = 14 K, where the magnetocrystalline anisotropy shows strong easy-plane characteristics, as established from measurements of the specific heat, ac susceptibility, magnetisation and electrical transport.
In order to investigate the magnetic structure we performed...
Gram(-) bacteria are pathogenic microorganisms whose outer membrane of the external envelope is composed of lipopolysaccharides (LPS), consisting of three structural domains: lipid A, the core oligosaccharide, and the O antigen. They are endotoxins responsible for many infections induced by bacterial pathogens, so represent a suitable target for selective detection. This can be achieved...
Non-lamellar lipid aqueous phases, such as reverse cubic or hexagonal phases, have increasingly been used to entrap biomolecules. We here discuss encapsulation of two key types of enzymes of different sizes, namely Aspartic protease (34 KDa), Beta-galactosidase (460 KDa) as well as heme proteins of importance for e.g. food iron supply. Although the curvature of the lipid aqueous interfaces in...
In the field of continuous low energy particle beams, Faraday cup detectors have been traditionally considered a way of precisely assessing the particle flux, given a few minutes of integration time and assuming no spatial resolution is required. Two years ago we presented a novel Faraday cup design, pursuing the aim is of providing fast and position-sensitive measurements. We will present now...
Structurally complex materials provide many different possible trapping sites for positrons. Especially, positron lifetime spectra of samples with µm and sub-µm sized grains must be carefully analysed, as positron trapping and annihilation in grain boundaries plays an increasingly important role and cannot be neglected anymore, even when other defect types are in the primary focus. To properly...
The increasing progress in developing next generation thin-film solar cells for space is shifting the focus of research towards practical implementation issues. Among the different types of next generation solar cells, in particular perovskite solar cells are gaining an increasing attention for space use. Meanwhile, first perovskite materials and devices have been tested in space. In contrast...
Polycrystalline CoNiCr-based alloys show promising properties for future high temperature applications due to their potential to achieve a high y'-volume fraction while retaining a significant processing range. The growing importance on emission reduction through innovative propulsion technologies, such as hydrogen-based aviation fuels or water-enhanced turbofans, requires research into how...
Magnetic skyrmions are topologically stabilized spin configurations on the nanoscale which makes them promising for next-generation information storage technologies and computing. [1,2] In magnetic multilayers, they can be stabilized at room temperature [3]. Skyrmions emerge due to an interplay between several magnetic contributions. Among them the interfacial Dzyaloshinskii-Moriya Interaction...
Human civilization is expected to face a huge challenge in the form of climate change in this century. One of the factors affecting this change is the use of fossil fuels, which have to be supplanted by so-called ’renewable energy sources’. Hydrogen is one of many possibilities for this energy storage, but a potent solution for storing the hydrogen is still being explored [1].
In this...
Smart copolymer microgels based on acrylamides are promising for several applications [1,2] Therefore these systems are intensely studied in recent years. If microgels are made with (photo-)crosslinkable comonomers (secondary crosslinkers), they can be deposited in thin layers and subsequently be cross-linked by irradiation [3,4]. Upon cross-linking freestanding membranes are obtained, which...
European Cultural Heritage (CH) is a crucial resource favoring social inclusion, job creation, and promoting resilience of our society against the emerging issues of the 21th century. Works of art interacting with the environment are prone to aging and decay. Soiling is a prime factor in the degradation of surfaces, chemical and mechanical degradation are often associated to soiling and lead...
The structural coexistence of dual rigid and mobile sublattices in superionic Argyrodites yields ultralow lattice thermal conductivity along with decent electrical and ionic conductivities and therefore attracts intense interest for batteries, fuel cells, and thermoelectric applications. However, a comprehensive understanding of their underlying lattice and diffusive dynamics in terms of the...
The study of geometrically frustrated systems with antiferromagnetically ordered spins on a two-dimensional lattice has recently gained considerable attention for their exotic quantum magnetic properties. In order to explore effects related to quantum magnetism we recently focused our attention to Na2BaMn(PO4)2. So far previous works on the isostructural Na2BaCo(PO4)2, a Co spin-1/2 compound...
Lithium metal is considered as one of the most promising anode candidates for high-energy batteries [1]. However, safety concerns induced by the formation of Li dendrites and the high reactivity at the electrode/electrolyte, resulting in a continuous electrolyte decomposition hinder the practical application [2]. It is anticipated that the use of non-flammable inorganic solid-state...
Hole doped transition metal oxides have been extensively investigated due to their many active degrees of freedom such as charge, spin, and orbital ordering. An interesting alternative to metal substitution in nickelates, e.g., RE2-xSrxNiO4, is achieved by oxygen doping, yielding RE2NiO4+d. The extra oxygen atoms have been evidenced to be mobile down to ambient temperature, adding an extra...
V-based oxides are attracting much interest as promising next-generation electrodes due to the vast resources in the Earth's crust, their unique open structures for fast diffusion with outstanding electrochemical properties and various oxidation redox couples. A recent review has debated if they “will become the future choice for ion-metal batteries”.[1] H2V3O8 allows reversible two-electron...
Increased attention to sodium-containing materials during the last years is caused by the rapid development of sodium-ion batteries (NIBs), which are considered as a potential successor for lithium-ion batteries (LIBs). Especially layered sodium oxides with transition metals have gained large interest due to their potential applicability as cathode materials. Similar to LiCoO2 in LIBs, NaCoO2...
Macromolecules in biological systems in vivo are in the cell's crowded environment, which can modify biological function through changes in the structural conformation with respect to diluted conditions. The structural characterization in crowded media is challenging given the high concentration and the intrinsic complexity in these samples. To address the topological effects, we use model...
Investigating nuclear structure parameters is a crucial in low-energy nuclear physics. The comprehension of gamma transitions, level schemes, nuclear level density, and radiative strength functions is necessary for both fundamental and applied research. To this end, the two-step gamma cascades method, involving the detection of gamma coincidences subsequent to neutron capture, specifically the...
Neutrons are a unique probe for non-destructive structural studies of energy materials, especially for the development of highly dense hydrogen stores. Thus, nano-porous materials have attracted great attention for gas storage, while the storage capacity still remains challenging. Here a magnesium borohydride framework with small pores was investigated and a unique partially negatively-charged...
Antimony selenide (Sb$_2$Se$_3$) is photovoltaic material with an optimal bandgap and a high optical absorption coefficient comprising of earth abundant elements. Solar cell power conversion efficiencies initially increased markedly but more recently the rate of increase has slowed. There is a large open circuit voltage consistent with the presence of detrimental concentrations of point...
