2D dimensional ptychograpy in Bragg geometry is powerful synchrotron radiation technique to study the shape and strain of the nano-objects. We applied 2D ptychography to determine the axial displacement field of single core-shell-shell semiconductor nanowires (NWs). The NWs were grown on silicon (111) substrates and are radially composed of a 140 nm GaAs core, 10 nm In0.10Ga0.90As shell and a...
Laminography enables non-destructive 3D imaging, achieving high resolutions with multiple contrasts for selected regions of interest even for large and laterally extended samples exceeding the view field. We continuously progress in the theoretical description of the methodology, in the construction of dedicated instrumentation, the measurement procedures, and the algorithms for data...
For the High Energy Density (HED) instrument at the SASE2 - Undulator at the European XFEL an x-ray split-and-delay unit (SDU) is built covering photon energies from h$\nu$ = 5 keV up to h$\nu$ = 24 keV. This SDU will enable time-resolved x-ray pump / x-ray probe experiments as well as sequential diffractive imaging on a femtosecond to picosecond time scale. Further, direct measurements of the...
Self-organized anodic titania (TiO2) nanotube arrays are an interesting model anode material for use in Li-ion batteries owing to their excellent rate capability, their cycling stability and their enhanced safety compared to graphite. A composite material where carbothermally treated conductive TiO2 nanotubes are used as support for a thin silicon film has been shown to have the additional...
The future-shaping properties of next-generation solar cells can potentially be achieved through an inorganic-organic hybrid photovoltaics (HPV) approach. Essential for a functioning HPV device is efficient charge separation at the interface between inorganic and organic material.
Due to titania being a wide-bandgap semiconductor and having good electron mobility, it is viable as a mesoporous...
Present day reactor based neutron backscattering spectrometers routinely achieve sub-$\mu$eV energy resolution with Si 111 monochromator and analyser, but are limited in energy transfer range to a window of typically $\pm 30~\mu$eV. Current scientific applications of this technique from various fields of e.g. energy materials, biology, or glass formers, are dealing with complex systems that...
Powder diffraction is a standard tool for characterisation in a wide range of fields across the physical sciences: from materials science and metallurgy, to chemistry and solid state physics. Third generation synchrotron sources provide high fluxes of X-rays at higher energy than laboratory sources. These characteristics open the door not only to rapid data collection for high...
The Coherence Applications Beamline P10 at PETRA III is dedicated to coherent X-ray scattering experiments using X-ray Photon Correlation Spectroscopy (XPCS) and Coherent Diffraction Imaging (CDI) techniques as well as time-resolved studies of complex liquids (Rheo-SAXS).
Mostly, the beamline operates in the energy range of 5-17 keV. It consists of two 12m long experimental hutches (EH1 & EH2)...
Neutron diffraction on a triple-axis spectrometer and a small-angle neutron scattering instrument is used to study the magnetic phase transition in tetragonal Ba$_2$CuGe$_2$O$_7$ at zero magnetic field. In addition to the incommensurate cycloidal antiferromagnetic (AFM) long-range order, we establish that weak incommensurate ferromagnetism (FM) also arises below the transition temperature...
With the construction of the high power European Spallation Source (ESS) and the dwindling of reactor based neutron sources in Europe and the US, the neutron user community is facing a mixed outlook towards the availability of neutrons in the coming decades. Accelerator driven neutron sources with high brilliance neutron provision present an alternative to the classical neutron sources to...
For years, carbon nanostructures have played a prominent role in case of electrochemical energy storage. Especially carbon nano onion films as a conductive additive for supercapacitors can be implemented to improve electrical characteristics. These onions with an almost spherical shape consist of several enclosed fullerene-like carbon shells. Amongst various ways to synthesize these onions,...
Additive Manufacturing (AM) offers the opportunity to produce easier geometrically complex parts compared to traditional production technologies. An important AM technology for metals is selective laser melting (SLM) where a part is produced by melting and solidifying powder in layers. This technique is known to cause a pronounced texture in the produced AM products due to the specific heat...
Colloidal quantum dots (CQDs) have been attracted many attentions on various electronic applications, like light emitting diodes (LEDs), photo detectors (PDs), photovoltaics (PVs) etc. due to their unique intrinsic properties, like tunable energy band-gap, stability against ambient circumstance. Comparing with cadmium chalcogenides CQDs, the lead chalcogenides CQDs reveal much weaker exciton...
X-ray emission and x-ray Raman scattering spectroscopy are powerful tools to investigate the local electronic and atomic structure of high and low Z elements in situ and can be applied at high pressure and high temperature conditions which are present in e.g. the Earth's mantle. We developed a setup for simultaneous x-ray emission (Fe Kß$_{1,3}$ and valence to core) and x-ray Raman scattering...
The self-assembly of small unilamellar vesicles (SUVs) in mixtures of perfluorinated and hydrocarbon surfactants has been subject of intense studies in the past with a focus on the phase diagram [1,2], shape and kinetics of the aggregates depending on concentration and mixing ratio [3] as well as control thereof [4].
Given that the scattering length densities (SLD) of perfluorinated and...
We report on a study of critical scattering in classical and nearly quantum critical antiferromagnets (AFs). The energy width of the critical scattering was determined by high-resolution neutron spin-echo at TRISP at the MLZ. The classical systems studied include the s=5/2 AFs MnF2 and Rb2MnF4 with quasi 2D and 3D spin interactions, respectively. Discrepancies between experiment and theory...
The proximity effects in superconducting/ferromagnetic (S/F) systems are attracting nowadays great attention in basic and applied research due to the presence of unique properties. Typically the S/F systems consisted of F layers with rather strong exchange energy (100-1000K) in contact with much weaker (10-100K) superconductors. In this sense it is straightforward to expect strong influence of...
Solidification from undercooled melts, either crystallisation or glass formation, is an important physical phenomenon of great technical and academic interests. Properties of the solid materials depend crucially on the solidification conditions. The competition between crystallisation and glass formation determines the stability of the undercooled melt and its glass forming ability.
We...
The European Spallation Source (ESS) is expected to be the world’s most powerful neutron source. Among the endorsed instruments foreseen for day one instrumentation at ESS, is the cold time-of-flight spectrometer CSPEC, collaboration between the Technische Universität München, and the Laboratoire Léon Brillouin. The high performance cold time-of-flight-spectrometer will serve a broad user...
The coincident Doppler broadening (CDB) spectrometer at the positron beam facility NEPOMUC of the research neutron source FRM II enables depth dependent and spatially resolved defect studies by using Doppler broadening spectroscopy (DBS), and element-specific measurements with coincident DBS. In order to investigate the near-surface region and the bulk of a sample, the positron implantation...
Modern neutron Multi-Wire-Proportional-Chambers operating with alternative solid-state converter as $^{10}B_{4}C$ coatings have the potential to surpass the position resolution and count rate capability of $^{3}He$ based detectors at comparable detection efficiency [1, 2]. The use of large area converter coatings on sub-mm substrates makes it essential to develop a mechanical concept to avoid...
The High Brilliance neutron Source (HBS) project [1] aims for the development of compact, scalable, accelerator driven neutron sources. These are needed to facilitate the installation of a network of low to medium flux sources in Europe and close the developing supply gap for science and industry.
The NOVA ERA (Neutrons Obtained Via Accelerator for Education and Research Activities) [2] branch...
At the moment, with the construction of the European Spallation Source ESS in Lund, the most modern and most powerful scientific neutron source in the world is being built.
The aim of our composite project “FlexiProb” is to develop three different sample environments for the investigation of soft matter samples to maximize the potential of the new neutron source with regard to the expected...
Superalloys are widely used for high temperature applications like gas turbines. For this reason these kinds of alloys require specific optimized mechanical properties which they receive from solid solution strengthening, particularly precipitation strengthening. The strength strongly depends on type, shape and size of the respective precipitates. For the improvement of such materials it is...
Vesicle shape and bilayer parameters of 1,2-dimyristoyl-sn-glycero-3-phosphocholine based vesicles are studied by small-angle X-ray (SAXS) and small-angle neutron (SANS) scattering in the presence of the natural surfactant (saponin) aescin [1]. We confirm successful incorporation of aescin molecules by analysis of the radii of gyration of the vesicles which we use as model systems....
Due to the reversible temperature induced volume phase transition (VPT), PNIPAM microgels serve as model systems for basic research. Moreover, the variation of the chemical composition tunes the functionality and responsivity. Changing the monomer feeding process influences homogeneity of the polymer particles and changes structure and dynamics of such systems. The classical particles...
Organic solar cells have attracted increased attention due to their advantages in tunable characteristics, low-cost manufacturing processes and flexibility, which opens up a promising alternative for conventional photovoltaics. Recently, the most widely investigated bulk heterojunction donor-acceptor system of P3HT:PCBM was doped with iron oxide nanoparticles, resulting in an increased...
Spectroscopy of few electron heavy ions is a unique testbed for both atomic physics, especially the test of quantum electrodynamics in strong fields, as well as for tackling astrophysical questions. The energy resolution of such measurements is limited by the use of standard semiconductor detectors. Currently, there are two ways to improve the energy resolution under investigation: on one side...
The need for rapid data collection and studies of small sample volumes in the range of mm3 are the main driving force for the concept of a high-throughput monochromatic diffraction instrument at the Heinz Maier-Leibnitz Zentrum (MLZ). A large section of reciprocal space will be addressed with sufficient dynamic range and µs time-resolution while allowing for a variety of complementary sample...
Hybrid Ferromagnetic/Graphene (FM/Gr) systems enclose remarkable technological opportunities by bridging spintronics with promised ultra-fast Gr-based electronics and photonics. These are also of fundamental relevance since Gr actively interacts with the neighboring materials determining a modification of the electronic and magnetic properties of the system. In particular, Graphene-spaced...
Given the vast array of natural synthesized proteins, the degree of folding, mechanism, location of assembly and size of the protein varies greatly. Amid this multitude of proteins, the ferritin family of proteins, considered bionanocages can be classified by size. The DNA-binding proteins from starved cells (DPS) are under 10 nm in diameter and part of this family. These bionanocages are...
In nuclear resonant scattering (NRS) experiments the nuclear decay following the excitation of the sample by a synchrotron radiation pulse is monitored by fast avalanche photo diodes (APD) [1]. In this presentation we focus on recent developments on a 16 element APD detector, the application of a fast time to digital converter (TDC) [2] for enhanced pulse detection, and a fast digitizer for...
Recently we demonstrated enhanced sensitivity for the investigation of magnetic films with low magnetization about 100 G using a new method, namely polarized neutron channeling in planar waveguides [1]. Such films containing rare-earth elements are promising materials for magnetic recording and switching and nearly inaccessible for the conventional polarized neutron reflectometry because of...
The fine-resolution neutron powder diffractometer E9 [1] at the BER II research reactor at the Helmholtz-Zentrum Berlin für Materialien und Energie is dedicated to collect high quality diffractograms suited for crystal structure determinations and Rietveld refinements.
The detector bank consists of eight individual 2D detectors, arranged at an optimized, non-constant distance from the sample,...
Fourth generation synchrotrons like MAX IV in Lund, Sweden, provide a brilliance gain of about two orders in magnitude. This puts new challenges on the fabrication of optics, sample stages, detectors, and data analysis chains. Here we focus on the focusing properties of the Kirkpatrick-Baez mirror system at the NanoMAX beamline [1], and present recent commissioning results.
We compare...
Understanding of the kinetics of phase separation is of importance for numerous systems, for example to control demixing processes. The thermoresponsive polymer Poly(N-isopropylacrylamide) (PNIPAM) may serve as a model system to investigate the kinetics of phase separation. In aqueous solutions at temperatures above the cloud point, PNIPAM forms stable mesoglobules with a size and degree of...
Positron annihilation lifetime spectroscopy (PALS) is a powerful tool in a wide range of material science. To investigate inhomogeneous defect distributions, e.g. close to fatigue cracks or dispersive alloy, with PALS a monochromatic pulsed positron beam of variable energy with a diameter in the range of 1 µm and a pulse width of 150 ps FWHM is needed.
In order to achieve this beam quality...
Fragment screening has been developed into a routine method in the drug discovery process. Compared to high-throughput screening, fragment libraries can be much smaller in size and are therefore amenable to crystallographic screening, either directly or after a suitable prescreening method. Particularly, synchrotron beamlines, such as MX14-2 at Helmholtz-Zentrum Berlin, dedicated to fragment...
A pair plasma produced of electrons and positrons will enable novel studies of many facets of fundamental plasma physics, in addition to being of great astrophysical relevance. The main bottleneck in producing this exotic system in a laboratory is the command over a sufficient number of positrons. We are therefore using the NEPOMUC positron beam line at FRM II for our project. For our plasma...
GISAXS is a powerful tool to provide information about the size, shape and structural ordering of nanostructures. For evaluation of the experimental 2D patterns an appropriate software is needed. In this work we study nanostructures with well defined form and structure factors which will be used as reference samples. The main aim of the studies is to prepare the BornAgain software package to...
New approaches are needed for the fast, non-destructive dimensional measurement of complex nanostructures in the semiconductor industry. One technique being considered is Small-Angle X-ray Scattering (SAXS), which has already been used in transmission geometry to reconstruct the line profile of gratings with low uncertainties. Grazing-Incidence SAXS (GISAXS) in reflection geometry additionally...
Transition metal oxides are interesting materials to study the complex interaction between electron spin, charge, and orbital ordering. One such oxide is the cubic spinel ferrimagnetic magnetite (Fe$_{3}$O$_{4}$), exhibiting high Curie temperature ($\sim$860 K) and a characteristic Verwey transition at 120 K leading to an abrupt increase in its resistivity. The half-metallic ground state (100%...
VO$_2$ films on the relaxor ferroelectric Pb(Mg$_{1/3}$Nb$_{2/3}$)$_{0.72}$Ti$_{0.28}$O$_3$ (PMN-PT) provide a promising candidate for the realization of a “Mott-tronic” device. VO$_2$ undergoes a first-order structural phase transition at about 340 K and simultaneously switches from insulating to metallic behavior by a five orders of magnitude resistance drop. Importantly, the...
Accessing structure beyond pair correlation functions is expected to shed light on various open questions in condensed matter physics such as the glass transition phenomenon. Typically, it is governed by the appearance of dynamical heterogeneities, suggested to be closely connected to spatial heterogeneities. Such spatial motifs are believed to play a key role in the glass transition process,...
Beamline P64 is dedicated to XAFS-experiments which require high flux like QEXAFS on the 10ms time-scale, EXAFS of highly diluted systems, and resonant high-resolution x-ray emission spectroscopy. We will present the optical set-up of the beamline (undulator, monochromators, mirrors, detectors), characteristics of these components, describe different operation modes for EXAFS-scans (continuous...
One way to store hydrogen is the use of Reactive Hydride Composites (RHCs), like Ca(BH4)2-Mg2NiH4. These materials have high capacities and suitable kinetics for hydrogen storage. On the other hand, the challenges of these compounds are the high pressures and temperatures, needed for hydrogen absorption and desorption. Ca(BH4)2-Mg2NiH4, e.g., requires 400 bar H2 and 450°C. Tanks used in...
Co-Re-based alloys [1] are developed to supplement single crystal Ni-based superalloys in future gas turbines. Addition of boron to the Co-Re-based alloys largely increases their ductility [2] and is thus advantageous. On the other hand, the stability of the matrix at the foreseen metal operation temperatures (≥1200°C), which can be influenced by the presence of boron, is also an important...
High current liquid metal ion sources are versatile investigated and found their first application as field emission electric propulsion (FEEP) thrusters in space technology [1]. Due to the available ion current in the µA-range such kind of sources are also well suited for broad ion beam technology. LMAIS are also nearly the only type of ion sources delivering polyatomic ions from about half...
Reduced capacity and rate capability, lithium plating and current collector corrosion are some of the effects detrimental to lithium-ion battery performance and safety at low temperature operation. Novel electrode designs and electrolytes that suit these conditions are currently investigated. Detailed knowledge of the effect of low temperature conditions on the battery during operation is...
Ni-base superalloys, well known as high-temperature alloys, are used in gas turbines (both stationary for electric power generation and in aircraft). They fulfill the requirements of high-temperature strength, ductility, corrosion resistance and high creep resistance needed in these applications and have a stable microstructure. Due to the fact, that the service temperature already reached 80%...
Nanometric Cu/W multilayers deposited onto Si substrates by RF ion beam sputtering experience a complex residual stress state that arises during deposition and depends on a range of parameters. In addition, the high density of bi-material interfaces in multi-layered systems along with the high volume fraction of grain boundaries within the nanocrystalline layers lead to a large increase in the...
The investigation of uniaxial and triaxial stress states in geological samples serves to a better understanding of the rock behaviour. The application of neutron time-of-flight diffraction allows the study of applied and residual strain of bulk rocks. The neutron time-of-flight strain diffractometer EPSILON at IBR-2M is equipped with a new triaxial pressure device “TRIXI” to investigate...
Many proteins contain a chromophore or metal centre with absorption bands in the UV/VIS spectral region. The details of the absorption bands report on the state of the protein, like different oxidation or conformation states. In X-ray crystallography, the absorption may even reflect radiation damage during data collection. Especially in high-resolution data collection, alterations in the...
Understanding the molecular mechanism of adsorption in porous materials is important for a broad range of modern technologies staring from energy storage and conduction to heterogeneous catalysis and to the development of the novel drug carriers. Recent theoretical studies hint at adsorption induced structural changes and the onset of stress in porous materials contradicting broadly accepted...
Incommensurate magnetic structures like Helimagnons and Skyrmions are currently intensively studied. Due to their large size compared to the lattice constant they show excitations at very small q, where most of the interesting physics is taking place below one meV. The cold-neutron three-axis spectrometer MIRA with its excellent intrinsic q resolution makes it ideal for studying such...
Various chiral spin structures, stabilized by the antisymmetric Dzyaloshinsky-Moriya interaction (DMI), are known to occur in the cubic chiral magnet MnSi. Strongly coupled, low-energy helimagnon bands are a universal characteristic of chiral systems and were studied in the presence of multiple domains [1] and the single domain phase [2]. Furthermore, a non-reciprocal magnon dispersion...
Cell membranes play a fundamental role in protecting the cell from its surroundings, in addition to hosting many proteins with fundamental biological tasks. Drugs are able to perturb the structure of cell membranes, which can ultimately give rise to undesirable effects. Thus, a study of drug/lipid interactions is a necessary and important step in fully clarifying the role and action mechanism...
Rare-earth metals exhibit the highest magnetic moments among all atomic elements and show delicate magnetic ordering and concomitant complex photo-induced dynamics. We studied the fluence-dependent magnetization dynamics in Gadolinium (Gd), Terbium (Tb), and in bilayer systems combining both metals, grown on a W(110) substrate. For our investigations the FemtoSpex slicing facility at the...
During protein folding different intermediate states occur with varying content of secondary structural elements. Regions lacking well-defined structure exist as well in unfolded and partially folded systems. In order to characterize their dynamics, we studied apo-myoglobin in different folding states [1,2,3]. We investigated internal dynamics of its unfolded form on a time-scale up to...
Electrical steel sheets are used in transformers as well as in electrical motors to guide the magnetic field. The efficiency of an electrical steel sheet strongly depends on the amount of energy lost during the reversal of magnetization, which is dependent on the mobility of the magnetic domains. The mobility of the magnetic domains is mainly influenced by internal stress caused during the...
The adsorption of molecules on vanadium oxide surfaces has been studied extensively, due to their widespread use in industrial catalysis. X-ray photoelectron spectroscopy (XPS) provides detailed information on the chemical bonding states of adsorbed molecules, and how they influence surface properties. However, previously existing XPS studies of molecules on vanadium oxide surfaces were...
Titanium alloys have plenty of applications in industry and medicine due to unique combination of high strength, low density, and excellent biocompatibility [1]. Here, we would like to demonstrate results of investigations of Ti-15Mo (wt.%) alloys using small-angle neutron scattering (SANS). These alloys contain metastable ω (hexagonal) and α (hcp) precipitates in β-phase matrix. The resulted...
The particular innovative potential of the SFB 986 is its ability to develop macroscopic materials – structured in a multi-scale way, designed “on the drawing board”. Scattering techniques are a powerful tool to investigate these materials on several length scales.
Due to their different sensitivity to the included phases, SAXS (P07 at PETRA III, Hamburg) and SANS (SANS-1 at FRM II, Garching)...
Structural and dynamical properties of surfaces and interfaces are of pivotal importance for the elucidation of surface phenomena. For example, chemical reactions at surfaces and interfaces are influenced by these properties. Here, we perform optical pump – X-ray probe measurements from liquid-air interface using LISA diffractometer [1], for the first time, installed at P08 beamline at the...
Genetically encoded FRET-based biosensors have been developed as a tool to quantify metabolites in living cells. The sensors consist of a central metabolite binding protein and flanking fluorescent GFP proteins affixed by different linker sequences.[1] Fluorescence measurements are sensitive either to distance or orientation changes of GFP domains as response to glucose binding. They were used...
Photosynthesis is one of the key mechanisms for “energy generation” in nature. It is controlled and driven by photoactive proteins. Their functionality is critically influenced by molecular movements in the range of ps – ns and sub-Å – nm. For comprehensive investigations of such systems it is necessary to gain information about the connection of their dynamics and functionality during and...
Phase and structural behaviour of the continuous perovskite solid solution Pr1-xSrxAl1-xTixO3 have been studied in the temperature range 20 – 295 K by high-resolution X-ray synchrotron powder diffraction. Superb characteristics of the beamline ID22@ESRF allows to detect either subtle spiting of the main perovskite maxima and/or appearance...
The need for pharmaceuticals based on therapeutic proteins is increasing for many years. Here, the purification is the most cost-intensive step during the production of therapeutic proteins which leads to remarkable potentials in the improvement of common techniques. Besides adaption of purification resin, affinity tags can be used to selectively separate target proteins from contaminations....
Geometrically frustrated spin systems comprised of e.g. zig-zag chains, triangles, or pentamers of MO6 (M = 3d-metal cations) often show magnetoelectric (ME) coupling effects fundamental in multiferroics. Many phosphatic oxyhydroxides exhibit such interesting moieties of MO6. Besides, they contain hydrogen networks of OH- and HOH-groups, showing various strengths of hydrogen bonds, such as...
The Magnetocaloric Effect forms the basis of magnetocaloric refrigeration technology, which is a novel energy efficient and environmentally friendly method for cooling [1]. MnFe4Si3 is an interesting magnetocaloric material, which features a modestly large magnetic entropy change as it contains only environmentally unproblematic and abundant elements; it has also some application relevance....
Quantum mechanical calculations of the ground state energy in pure electron gases reveal a mechanical instability, if they are sufficiently expanded. Appropriate scaling allows relating these gas densities to mass densities in real liquid alkali metals which are regarded as perfect model systems for free electron gases. It is found that the region of instability corresponds to 3-4 times the...
For the analysis of solution small-angle scattering data of proteins a wide selection of software such as Crysol [1] exists. In the strict sense they are only designed for pure protein structures. Many proteins, however, come with modifications such as fatty acids, glycosyl groups [2] and bile acids [3].
In a few cases such modifications could be accurately modeled together with their...
Hybrid organic-inorganic halide perovskites $\rm{CH_3NH_3PbX_3}$ ($\rm X=I,Br,Cl$) are promising novel materials for the application in future photovoltaics (PVs), with a tunable absorption characteristic and efficiencies comparable to silicon. Since solution-based fabrication techniques and the use of flexible substrates are possible, perovskite PVs are potentially low-cost and could find...
In optoelectronic devices based on quantum dot arrays, thin nanolayers of gold are preferred as stable metal contacts and for connecting recombination centers. The optimal morphology requirements are uniform arrays with precisely controlled positions and sizes over a large area with long range ordering since this strongly affects device performance. To understand the development of gold layer...
Dye-sensitized solar cells (DSSCs) offer outstanding potential due to their minor investment compared to inorganic solar cells and higher stability compared to organic solar cells. In this kind of cells, nanostructured inorganic metal oxides with tunable morphologies are of great importance. Among the many inorganic metal oxides, ZnO has been widely explored due to its outstanding electrical...
Bulk heterojunction (BHJ) organic solar cells have gained significant improvements via novel organic synthesis methods and optimized fabrication routes, especially with respect to their potential roll-to-roll processing for large-area device manufacturing. Printing techniques allow for up-scaling to industrial-oriented scale which is not the case for laboratory deposition techniques like spin...
Thermoelectric materials pose a compelling technology for power generation from renewable energies, since temperature gradients are transformed into voltages and thus electrical power. So far, highly efficient thermoelectrics comprise rare and/or toxic inorganic materials, and require cost- and energy-intensive fabrication. These points hinder their large-scale application.
In order to...
The preparation of superconducting Nb-cavities for particle accelerators comprises several treatments including e.g. buffered chemical polishing, electropolishing, high pressure rinsing and dry-ice cleaning. Recent experiments have shown that the RF-superconducting properties of the Nb-cavities can substantially be improved using heat treatments under dilute nitrogen or argon atmospheres,...
Non-destructive X-ray spectrometry methods such as XRF, TXRF as well as GIXRF/GEXRF allow determining the elemental composition of unknown bulk and layered samples. However, in most cases well-defined standard or reference samples are required if quantitative information about layer thickness (nm) or mass deposition (ng/mm²) shall be deduced from the fluorescence radiation (cps). Internal or...
The high brilliance laboratory small angle X-ray scattering instrument GALAXI [1] is used to investigate, on mesoscopic length scales, structural correlations in bulk materials or between objects deposited on a surface. The instrument is capable to perform GISAXS experiments in reflection at grazing incidence as well as SAXS experiments in transmission geometry. The X-ray flux on sample is...
Lithium-ion batteries (LIBs) have been widely used in many aspects of modern life. Compared with conventional graphite anodes, TiO2 possesses superior cyclic stability and environmental benignity. However, its moderate conductivity and lithium ion migration ability still need to be improved to realize further development. As alternative anode material, SnO2 afforded much higher theoretical...
Modern particle accelerators rely on niobium RF (Radio-Frequency) cavities for their operation and there is a big drive for performance improvement of such devices. Achieving a higher quality factor (Q0), will lead to higher luminosity while reducing the dynamic heat load, resulting in potential cost savings. Nitrogen doping is known to increase the performance of niobium cavities [1],...
In operando observations of Li transport in all-solid-state thin-film batteries during fast (dis)charge cycling, as well as the study of mechanisms of battery aging become possible at a new Neutron Depth Profiling (NDP) setup of JCNS, using the focused neutron beam of reflectometer MARIA (MLZ). This arrangement allows for sufficiently high counting rates necessary for fast, about tens of...
One major limitation in neutron depth profiling is given by the signal to background ratio (S/B) especially using thick sample material or samples with high amount of absorbing elements. A high neutron flux for fast and time resolved measurements introduces typically a fast increase of beta activity in the sample material and dilutes the S/B ratio. Shielding techniques for beta particles and...
Together with the Helmholtz-Zentrum Berlin NOB has developed several kinds of neutron optical devices for polarization, collimation and focusing of neutron beams. In most of them the neutrons are transported in thin silicon wafers with coated walls.
Results are shown for solid state benders and a radial bender for the polarization of neutrons.
A solid state polarizing bender without absorbing...
Nanostructured thin films with embedded magnetic nanoparticles (NPs) are promising in magnetic applications due to their novel chemical and physical properties. The realization of desired magnetic properties depends on the arrangement of the NPs and can be tuned by employing diblock copolymers as host matrixes. Various ordered nanostructured templates can be achieved from the phase separation...
Redox proteins functions in many biological processes, such as metabolism, photosynthesis, respiration. The chemical reactions of redox proteins proceed with small structural changes involved in hydrogen atoms and/or valence electrons. Thus, high-resolution structure analysis revealing these small structural changes is necessary for understanding molecular mechanisms of redox reactions. NADH...
A new X-ray undulator beamline dedicated to HAXPES applications is now open for user operation at PETRA III (DESY, Hamburg). The beamline comprehends a unique selection of HAXPES techniques using specialized instruments built and operated in collaboration with external user groups. The main instrument is the established HAXPES setup relocated from PETRA III beamline P09. It provides an...
In the past, the structure of thin epitaxial films has been studied extensively by hard x-rays using dedicated systems at various synchrotron beamlines for in-situ studies [1,2]. The typical time scale for these experiments hasv been rather high forcing these studies to focus either on a rather limited parts of reciprocal space [3] or to accept rather poor time resolution. Using high energy...
Vibrational iron ligand modes of 57Fe labelled complexes can be accessed via synchrotron based nuclear inelastic scattering (NIS). First results of NIS experiments performed in October 2017 at PETRA III, DESY are presented and compared to simulations of the experimental partial density of vibrational states (pDOS). The influence of protonation on the vibrational properties of a...
The combination of nuclear forward scattering as time-domain synchrotron-based nuclear resonant scattering method with high-purity polarimetry is a novel approach to probe electronic anisotropies in metal-containing compounds ranging from biological molecules to solid state systems.
This method is based on exploring the polarization dependence of the nuclear hyperfine transitions at the 14.4...
The structures formed in self-assembling or self-organising systems can vary dramatically, and often non-linearly, depending on the processing conditions or as a result of external stimuli. In turn, these structural differences will often lead to pronounced differences in macroscopic properties and functionality. Optimisation of the functionality of such systems therefore entails increased...
Water splitting is one of the most promising routes for renewable energy conversion and storage. Iron group metal oxides, especially Co oxides, are promising candidates for noble metal free catalysts for the oxygen evolution reaction (OER). In order to design efficient and scalable catalyst materials the relation between the surface structure and the catalytic properties are of fundamental...
Metal-support interactions in Ru/TiO2 catalysts have a decisive impact on their catalytic activity and selectivity for CO methanation. These effects and the catalytic performance of the catalysts were found to change upon varying the surface area of the support, which is not yet well understood. One approach to explain this change would be a change in the surface morphology of the TiO2...
X-ray absorption fine structure spectroscopy (XAFS) is among the most useful analytical methods for the investigation of structure/function relations in all fields of catalytic chemistry and energy storage techniques like batteries, fuel cells, H\textsubscript{2} storage etc. The beamline was build as part of the PETRA III extension project and is in regular user operation since Summer 2016....
The first works on the new beamline P66 design has been started 5 years ago as a part of PETRA III extension project [1]. At the very beginning of the project the main idea was to relocate very successful experimental station for time and spectrally resolved luminescence investigations from DORIS to the PETRA synchrotron source. The efficiency of the unique station SUPERLUMI at DORIS [2] was...
With the Arduino open hardware electronics platform microcontrollers have become a comparably easy-to-use tool for rapid prototyping and implementing innovative solutions. Their stability especially qualifies them to be used for slow control units. Yet, running at 16 MHz, the capabilities can be extended to data taking and signal analysis at decent rates. Such devices in combination with...
X-ray near-field holography (NFH) is a propagation based coherent phase contrast imaging technique which does not rely on an image forming optic. Implementing NFH in a divergent beam created by nano focusing optics allows the application for microscopy. The magnification and field of view are straightforwardly controlled by geometrical parameters. This allows the easy measurement of overview...
The evolution of thermal properties of samples irradiated with GeV Au and U ions at the UNILAC accelerator at GSI was studied using the photothermal radiometry (PTR) technique. PTR measurements allow a depth resolved measurement of the thermal properties of the irradiated samples. In the present study, this technique is applied to characterize the 50-70 µm thick damaged layer on swift heavy...
POLI is a versatile two axes single crystal diffractometer, mostly dedicated to the investigation of magnetic structures of single crystals using neutron spin polarization.[1] Unlike other short-wavelength polarized neutron diffractometers with Heusler-alloy monochromator for both polarization and monochromatization, POLI employed non-polarized double-focusing monochromators in combination...
Metal-Organic Frameworks (MOFs) – hybrid inorganic-organic porous crystalline materials with large and tunable pore structure, surface area and pore volume. The hierarchical pore structure of MOFs and tunable polarity of the inner surface make this class of materials attractive for the application in adsorptive heat pumps. Recently, a chemically stable microporous Zr-based MOF with composition...
Within the standard model of particle physics only two free parameters determine the decay of the free neutron, where we profit from the precise determination of the Fermi coupling constant in muon decay. These free parameters are the ratio of axial-vector and vector coupling constants $\lambda=g_A/g_V$ and the CKM mixing matrix element $V_\mathrm{ud}$. With about a dozen experimental...
Organic Solar Cells are a promising alternative to conventional silicon-based devices as they
offer several potential advantages e.g. low weight, high mechanical flexibility and low-cost production. Resent research focuses on identifying new high-efficiency polymers and acceptor molecules to reach high power conversion efficiencies.
To date, a Power Conversion Efficiency of 13% could be...
A fuel cell is one of the future promised power sources that produce electricity through an electrochemical reaction of hydrogen and oxygen without producing harmful products. Crosslinking PVA/SSA proton exchange membranes were prepared at different concentrations of SSA (5-30 wt.%) using casting technique. SO3 groups added by crosslinking with SSA are responsible for modifying the membrane...
Phenomena and effects on interfaces and in individual atomic layers play a key role in the modern material science, especially in the field of nanotechnologies (nanoelectronics, photonics, plasmonics, etc). The pulsed laser deposition (PLD) technique is a versatile tool with a capability of using a wide variety of materials to produce such structures. Neutron radiation offers a unique...
On-surface coordination chemistry is an emerging field that holds promise for applications in, e.g., nanotechnology, molecular spintronics and heterogeneous catalysis. Previous work provided evidence for a “surface trans-effect”, where the interaction [1] and even the magnetic coupling [2] between the metal ion of adsorbed metal-organic species and the underlying substrate can be affected by...
In most cases, bulk-type reference-materials do not provide optimal calibration schemes for the analysis of nanomaterials as e.g. surface and interface contributions may differ from bulk. Also, spatial inhomogeneities may exist at the nanoscale or the response of the analytical method may not be linear when going from bulk to the nanoscale. Thus, the availability of suited nanoscale reference...
RESEDA (Resonance Spin Echo for Diverse Applications) is a high-resolution resonance spin echo spectrometer, operated by the Technische Universität München. It is situated at the end of neutron guide NL5-S at the cold source of the FRM-II research reactor in Garching Germany [1]. In contrast to classical neutron spin echo spectrometers, RESEDA realizes the spin precession by resonance coils...
Friction Surfacing (FS) is a solid-state process, which allows deposition welding at temperatures below the melting range. It can be used, e.g., for property enhancement or repair purposes. The technique uses a consumable stud that is rotated and pressed on a substrate surface while moved forward. The combination of materials used for stud and substrate defines the windows of process...
Since 2010, the joint research project "Chemical Crystallography Beamline" is working together to build up a dedicated experimental station at DESY's PETRA III east extension in Hamburg. The partners from Freiberg contribute in particular by establishing the setup for Resonant X-Ray Diffraction methods. In addition to energy resolved photon detection and polarization analysis, this setup...
Recently, the existence of solvation shells around nanoparticles (NP) was given proof by pair distribution function analysis (PDF) in colloidal suspensions.[1] The building of solvation shells was found to be a universal phenomenon widely independent of capping agent, solvent polarity and particle size. However, a systematic study on how the single parameters influence this restructuring...
Lithium/sulfur (Li/S) and Lithium/air systems are possible candidates
for future electrochemical energy storage, due to higher gravimetric
density compared to conventional Li-ion batteries. In these systems, a
lithiated silicon (Si) electrode often replaces the Li metal anode, used
as a Li ions reservoir. Detailed studies on lithiation and delithiation
of Si anodes are of fundamental...
We present unique load frames which allow an orientation of the load axis by an Eulerian cradle type design and examples of their applications. One version is optimized for texture analysis allowing a free sample rotation around the phi axis under uniaxial tension or compressive stress. Thus complete pole figures under mechanical load can be derived. A second version enables torsion in...
The single crystal diffractometer HEiDi is designed for detailed structural studies related to physics, chemistry and mineralogy by offering high flux, high resolution and large q range, low absorption and high sensitivity for light elements using hot neutrons from FRM II at the Heinz Maier-Leibnitz Zentrum (MLZ).
In order to fulfil the various needs of our users the instrument offers a broad...
SAPHiR, the Six Anvil Press for High Pressure Radiography and Diffraction is a new instrument at the FRM II dedicated to neutron science at extreme pressure and temperature conditions. The three-axis multianvil press has a combined pressing force of 2400 tons (24 MN) and can perform experiments at up to 15 GPa in samples with volumes of 10-30 mm3. Applications include phase transformations at...
Vanadium dioxide undergoes a phase transition from an insulating, monoclinic (M1) phase at low temperatures to a metallic, rutile (R) phase above 68 ˚C. Since the two phases show distinctly different electrical conductivity and absorption in the near infrared VO2 is interesting for “smart” electrical and optical components or window coatings. Ion beam irradiation decreases the transition...
Beam-modulation techniques in X-ray imaging can serve for disentangling different contrast modalities, such as absorption, phase, and dark-field contrast. These encompass Talbot-grating interferometry of shadow mask (Hartmann) techniques. We have devised micro-lens arrays to be used as Shack Hartmann masks for dose-efficient, single-exposure imaging of dynamic processes.
The Shack-Hartmann...
The high brilliance of modern synchrotron radiation and X-ray free-electron laser sources allows studying the structure and dynamics of matter on relevant lengths and time scales. Creating small and intense X-ray beams is crucial to confine the beam and concentrate the radiation onto the sample. Ideally, this would require diffraction-limited X-ray optics with high numerical aperture (NA) that...
The development of new materials and the assessment of nanomaterials require the correlation of the materials’ functionality or toxicity with their chemical and physical properties. To probe these properties, analytical methods that are both sensitive and selective at the nano- and microscales are required. The reliability of most analytical methods is based on the availability of reference...
Grazing-incidence small-angle scattering (GISAS) is a powerful non-destructive technique to investigate nano- and layered structures deposited to the substrate. Nowadays, GISAS is increasingly used to study various soft matter systems.
The disadvantage of GISAS is the challenging data analysis that requires a simulation of the scattering process on a model of the sample. Simulation allows...
Semiconductor nanowires (NWs) are crystalline nanostructures which are
intensely researched in areas such as electronics, light-emitting devices, and
quantum optics. In particular, nanowire-based solar cells have shown strong
development in recent years [1,2]. While the mean crystal parameters can be
measured easily for large numbers of NWs, the strain/stress and bending of
individual NWs have...
The Small-K Advanced Diffractometer (SKADI) is a small-angle neutron scattering (SANS) instrument to be built at the European Spallation Source (ESS). It will enable scientists to perform experiments on questions requiring to investigate the microscopic structure of samples over a wide range of length scales and fast kinetic experiments.
SKADI’s design targets scientific areas of smart...
Polymer-based microgel and core-shell particles are versatile containers for the transport of drugs, theranostic gases or catalytically active molecules. They are in many cases biodegradable and fully compatible to in-vivo applications. During recent years we have investigated a broad range of such hybrid materials ranging from gas filled microballoons and thermoresponsible microgel networks...
Kesterite Cu$_2$ZnSnSe$_4$ (CZTSe) and chalcopyrite CuIn$_x$Ga$_{1-x}$Se$_2$ (CIGS) absorber materials can form high efficiency thin film solar cells. They feature a number of different polycrystalline layers with thicknesses of 10 nm up to several µm. Compositional variations of the absorber layer can limit their conversion efficiency. High resolution, spatially resolved investigations enable...
The sample environment activities play an increasing role in the BESSY II user service. The sample environment group, originally based at the BER II neutron source, is now fully established at BESSY II. It provides and supports various sample environment equipment for experiments at the source. In addition, it supports beamline scientists and synchrotron users in the design, construction,...
SrRuO3 is one of the very few perovskite metallic ferromagnets; it exhibits anomalous transport, an invar effect, non-Fermi liquid behavior, a magnetic shape-memory effect and it is an important substrate for various oxide heterostructures. Strong spin-orbit coupling (SOC) is visible in the invar effect and the large magnetic anisotropy. Recently, we could grow large single crystals of SrRuO3...
In the recent years the application of lithium-ion-batteries has attracted a greater interest for large scale applications such as electric vehicles (EV). Liquid batteries are already used and commercialized for such applications. This battery type has higher safety concerns in terms of leakages and flammability, especially in case of a crash. A good alternative with lower risks for drivers...
The myelin sheath is the membrane responsible for rapid signal transport in neurons. In multiple sclerosis, this membrane is damaged leading to neuron conduction failure. Myelin Basic Protein (MBP) which is the major structure protein of the myelin sheath has been proven to be an important factor in stabilizing the myelin sheath. In recent publications, a different lipid composition has been...
One main advantage of organic electronics is the potential of building flexible electronic devices. The polymer mixture poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) offers good electrical conductivity, transparency and inherent flexibility, which makes it to a promising alternative to rigid and brittle transparent electrodes like indium tin oxide (ITO). By different...
Structure and dynamics of confined liquids were probed by an in-situ X-ray surface force apparatus in plane-cylinder geometry. Our novel device can shear, compress and decompress soft matter within a precisely controlled slit pore confinement. Complementary structural information is obtained by X-ray scattering and simultaneous force measurements. Here, we present results on the structural...
The molecular structure of the white light generating amorphous material [(PhSn)4S6] is investigated using X-ray scattering coupled with a rigid molecular Reverse-Monte-Carlo (RMC) modeling approach. Experimental proof for an adamantane-like molecule structure is found. The intermediate-range structure is analysed, indicating a strong preference for distinct cluster orientations. It is shown...
Magnetic dumbbells consist of a noble metal seed linked to a magnetite nanoparticle. Self-assembly of nanoparticles in general, is of interest due to its broad range of applications in material science and biomedical engineering. Parameters that affect self-assembly of nanoparticles include particle size, thickness of surfactant and concentration but additional parameters such as composition...
Solid oxide fuel cells (SOFCs) are promising devices to generate clean energy efficiently. Numerous studies are currently underway to reduce the operating temperature of these cells from 800 - 1000°C to temperatures below 700°C (IT-SOFC). Perovskite type materials (ABO3) have generated great interest due to their excellent electronic conduction properties and good conduction by oxygen anions...
Monohydroxy alcohols have been scrutinized as a model of hydrogen bonded fluids. These hydrogen bonds are essential for the structure and dynamics of water, aqueous solutions and alcohols [1]. Monohydroxy alcohols are supposed to form supramolecular structures via hydrogen bonding in the liquid phase. We have investigated various alcohols by X-ray diffraction (XRD) over a temperature range...
Understanding the structural foundation governing the charge transport is the key for any rational design of electrochemical materials. In this respect, amorphous conductors such as ionic liquids (ILs) and polymer electrolytes are well investigated. At variance with other materials, the polymerized ILs (PolyILs) are prepared through direct covalent bonding of functional monomers containing IL...
Saponins are plant derived surfactants which occur e.g. in nuts and exhibit an amphiphilic structure built of a hydrophobic steroidic or triterpenic backbone with a varying number of hydrophilic sugar chains. Some saponins, including aescin, are used specifically for the relief of venous diseases e.g. varicose veins.
The interaction of aescin with model membranes composed of the phospholipid...
The Helmholtz-Zentrum Berlin with its expertise on high magnetic fields for neutron scattering has successfully installed a high field magnet (HFM) that has set a new record for static magnetic fields for neutron scattering. A magnetic field of 26.286 T was reached on October, 16th 2014. Since early 2015 the HFM is integrated in the neutron instrument ExED (TOF) representing a worldwide unique...
Cu(In,Ga)Se2 solar cells are the most efficient ones among all thin film photovoltaics. The recent push in record efficiencies was mainly realized by applying a RbF post deposition treatment (PDT) to the absorber. However, it is not yet fully clear why the introduced Rb improves the solar cell performance. In order to investigate the beneficial effect of Rb, a...
When a virus enters a host cell, the insertion of viral fusion peptides (FPs) into the target membrane catalyzes the membrane fusion reaction. While fusion intermediates with high membrane curvature appear in this process, the exact mechanisms of the peptide/membrane interactions remain unclear up to now. We investigated the insertion mechanism of different FPs into model membranes in X-ray...
The training and research reactor AKR-2 is a thermal, homogeneous, solid material moderated zero power reactor with maximum permanent power of 2 Watt. AKR-2 was completely refurbished in 2005 and is actually the most advanced zero power training reactor in Germany. The facility is equipped with a state-of-the-art digital I&C control system Teleperm XS (see also http://tu-dresden.de/mw/akr)....
The beam port MEPHISTO at the FRM II is dedicated for mostly long term experiments in the field of nuclear and particle physics. The first planned experiment at MEPHISTO is PERC. The author will present an overview of the parameters of the cold white neutron beam and its experimental area in the new east hall. This is based on the already existing neutron optics components, including the...
The shutdown of DORIS III discontinued some successful beamlines which served as main stations for a wide field of crystallographic applications ranging from diffuse scattering studies, charge density analysis, phase transitions, disordered and modulated structures all at ambient and non-ambient conditions.
A collaboration of a joint research BMBF project and Desy build up a new beamline at...
The neutron spin echo spectrometer provides the ultimate energy resolution in quasi-elastic cold neutron scattering spectroscopy. High-resolution means the extension of Fourier-time (τ) up to the regime of μs, which depends on the reduction of the field-integral inhomogeneity down to the some ppm. The limiting factor is the performance of the present correction coils. We could mitigate this...
Neutron depth profiling (NDP) uses neutron induced particle emissions to probe, for example, Lithium distributions within the first few micrometers of a sample, yielding valuable insights in fields like battery development. The Prompt Gamma Activation Analysis (PGAA) facility at the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching offers unique opportunities for high-sensitivity NDP by...
Introduction
Due to their high melting point, low density, and good oxidation resistance, γ-TiAl based alloys have recently started to replace Ni-based superalloys as a material for turbine blades in aircraft engines [1]. Conventional TiAl alloys usually contain the ordered phases γ-TiAl and α2-Ti3Al at lower temperatures and disordered α-Ti(Al) phase at higher temperatures. Additional...
Plant roots release a highly polymeric blend of substances called mucilage into the soil. Various alterations of soil hydraulic properties in their vicinity (the rhizosphere) have been attributed to the presence of mucilage. Despite its definition as a hot spot of microbial activity and the immense amounts of water (about 40% of all terrestrial precipitation) that cross the rhizosphere the...
Multiferroic properties have attracted much attention since they may have applications in electronic devices. Several models have been proposed to explain the mechanism of magnetoelectric effects such as the change of the modulation wavelength, and another key factor can be a noncollinear spin configuration which is in accord with the theory associated with Aharonov-Casher effect or the...
Layered transition metal oxides such as the ‘Li- and Mn-rich’ layered oxides, formed as the composites between Li2MnO3 and LiMO2 (M = Ni, Co, Mn) (NCM) are promising candidates for next generation Li-ion battery cathodes that offer high reversible capacities (> 250 mAh/g) and higher safety together with reduced costs. For an economic and efficient operation as cathode materials in electrified...
Self-propagating high-temperature synthesis (SHS) allows the synthesis of a large variety of compounds and new materials in an energy-efficient way. They have therefore been extensively studied and are well characterized with respect to the equilibrium thermodynamics.
In contrast, the characterization of the transient processes before, in, and after the reaction fronts have not been...
It is planned to install a ribbon-shaped high-density free-electron
target in the experimental section of the presently being
commissioned storage ring CRYRING@ESR of the upcoming Facility for
Anti-proton and Ion Research (FAIR) [M. Lestinsky et al., Eur.
Phys. J Spec. Top. 225, 797 (2016)]. Electron beam and circulating
stored ion beam interact under an angle of 90°. Recently, we...
The physical properties of ultra small clusters, such as magnetism, can differ fundamentally from the bulk material and are dominated by their confinement and atomic structure [1, 2]. The arrangement of such nanoparticles in a superlattice not only allows to reach high density and small size distribution, but it also enables new characterization approaches [2]. This is of great interest for...
The neutron-induced positron source Munich NEPOMUC provides a monochromatic positron beam of > 10$^9$ e+/s and ≈ 10 mm diameter FWHM. To create a small beam focus or sharp pulses of ≈ 100 ps the beam brightness needs to be enhanced by remoderation. This is achieved by focusing the beam magnetically on a tungsten single crystal W(100). Afterwards the beam exhibits an intensity of > 3 · 10$^7$...
The SPectrometer for High Energy RESolution (SPHERES) at MLZ is a third generation backscattering spectrometer with focusing optics and phase-space transform (PST) chopper. It provides high energy resolution with a good signal-to-noise ratio [J. Wuttke et al., Rev. Sci. Instrum. 2012]. Different components of the instrument have been upgraded to further improve the instrument performance....
Abstract
A vacuum-compatible hybrid pixel detector has been installed in the UHV reflectometer of the four-crystal monocromator beamline of the Physikalisch-Technische Bundesanstalt (PTB) [1] at the electron storage ring BESSY II in Berlin, Germany. It was developed in cooperation with Dectris and is based on the PILATUS3 100k module. The detector can be used in the entire photon...
Multi-stimuli responsive polymers can react with a strong change in volume towards small changes of an external stimulus, which makes them promising materials for a wide variety of applications. [1-3] While the underlying mechanisms of such polymers in solution are well understood, less is known about thermoresponsive polymers in thin film morphology. Regarding this context, the most studied...
We report on exploiting the X-ray magnetic linear dichroism (XMLD) contrast for probing the non-collinear states in a DyCo5 ferrimagnetic thin film. Utilizing x-ray magnetic circular dichroism which is sensitive to the magnetization of one elemental sublattice, an anomalous ’wing shape’ hysteresis loop is observed slightly above its compensation temperature. Based on the hysteresis shape, it...
Soft x-ray scanning transmission microspectroscopy (STXM) using Fresnel zone plates (FZPs) as focusing elements has developed into a routine technique for the investigation of semi-transparent thin film specimens. The x-ray absorption contrast is utilized as elemental or chemical fingerprint in multinary component specimens. Routine operation of STXMs uses spatial resolution of around 30 nm...
Modern automated beamlines are well suited for crystallographic screening of 100-500 entry fragment libraries or diverse subsets at no higher effort than alternative biochemical or biophysical pre-screening assays.
As an entry point for a direct crystallographic fragment screening and drug discovery, we compiled 96 well-suited fragments based on experience from prior fragment screening...
