A new high temperature, high heating rate, low axial gradient capillary heater.

A new heater design, capable of fast heating and cooling to and from >1000°C, has been developed at the Swiss-Norwegian Beamlines, European Synchrotron Radiation Facility, France. The design uses a SiC head to distribute heat, and resistive SiN heat cartridges to provide heat.

Preliminary observations of the interplay of radiation damage with spin crossover.

Intense synchrotron radiation makes time-resolved structural experiments with increasingly finer time sampling possible. On the other hand, radiation heating, radiation-induced volume change and structural disorder become more frequent. Temperature, volume change and disorder are known to be coupled with equilibrium in molecular spin complexes, balancing between two or more spin state configurations.

On the resolution function for powder diffraction with area detectors.

In a powder diffraction experiment the resolution function defines the instrumental contribution to the peak widths as a function of the Bragg angle. The Caglioti formula is frequently applied to model the instrumental broadening and used in structural refinement. The parameters in the Caglioti formula are linked to physically meaningful parameters for most diffraction geometries.

ROBL-II at ESRF: a synchrotron toolbox for actinide research.

ROBL-II provides four different experimental stations to investigate actinide and other alpha- and beta-emitting radionuclides at the new EBS storage ring of ESRF within an energy range of 3 to 35 keV. The XAFS station consists of a highly automatized, high sample throughput installation in a glovebox, to measure EXAFS and conventional XANES of samples routinely at temperatures down to 10 K, and with a detection limit in the sub-p.p.

Kinetic Barriers and Microscopic Mechanisms of Noble Gas Adsorption by Nanoporous γ-Mg(BH ) Obtained by Means of Sub-Second X-Ray Diffraction.

Gas adsorption by porous frameworks sometimes results in structure "breathing", "pores opening/closing", "negative gas adsorption", and other phenomena. Time-dependent diffraction can address both kinetics of the guest uptake and structural response of the host framework. Using sub-second in situ powder X-ray diffraction, three intracrystalline diffusion scenarios have been evaluated from the isothermal kinetics of Ar, Kr, and Xe adsorption by nanoporous γ-Mg(BH ) .

Crystal structure, chemical bonding, and electrical and thermal transport in ScRhSn.

Single crystals of ScRhSn were grown from Sn-flux. The crystal structure (SG: I4/acd, a = 13.5529(2) Å, c = 27.

Non-Isothermal Kinetics of Kr Adsorption by Nanoporous γ-Mg(BH) from in Situ Synchrotron Powder Diffraction.

Crystalline materials with pore dimensions comparable to the kinetic diameters of the guest molecules are attractive for their potential use in adsorption and separation applications. The nanoporous γ-Mg(BH) features one-dimensional channels matching this criterion for Kr uptake, which has been probed using synchrotron powder diffraction at various pressures and temperatures. It results in two coexisting crystalline phases with the limiting composition Mg(BH)·0.

A Room-Temperature Verwey-type Transition in Iron Oxide, Fe O.

Functional oxides whose physicochemical properties may be reversibly changed at standard conditions are potential candidates for the use in next-generation nanoelectronic devices. To date, vanadium dioxide (VO ) is the only known simple transition-metal oxide that demonstrates a near-room-temperature metal-insulator transition that may be used in such appliances. In this work, we synthesized and investigated the crystals of a novel mixed-valent iron oxide with an unconventional Fe O stoichiometry.

Thermal unequilibrium of strained black CsPbI thin films.

The high-temperature, all-inorganic CsPbI perovskite black phase is metastable relative to its yellow, nonperovskite phase at room temperature. Because only the black phase is optically active, this represents an impediment for the use of CsPbI in optoelectronic devices. We report the use of substrate clamping and biaxial strain to render black-phase CsPbI thin films stable at room temperature.

Crystal structure and superconducting properties of ScIrSn.

ScIrSn crystallizes with a split variant of the TbRhSn structure type (space group I4/acd, [Formula: see text] [Formula: see text], [Formula: see text] [Formula: see text]). DFT calculations confirmed the instability of the structural arrangement with the fully occupied and unsplit crystallographic sites. High quality single crystals were grown from a Sn melt.

Cornucopia of Structures in the Pseudobinary System (SnSe) BiSe: A Crystal-Chemical Copycat.

Pseudobinary phases (SnSe) BiSe exhibit a very diverse structural chemistry characterized by different building blocks, all of which are cutouts of the NaCl type. For SnSe contents between x = 5 and x = 0.5, several new phases were discovered.

Thermal and magnetic anomalies of α-iron: an exploration by extended x-ray absorption fine structure spectroscopy and synchrotron x-ray diffraction.

The local structure and dynamics of α-iron have been investigated by extended x-ray absorption fine structure (EXAFS) spectroscopy and x-ray diffraction (XRD) in order to shed light on some thermal and magnetic anomalies observed in the last decades. The quantitative EXAFS analysis of the first two coordination shells reveals a peculiar local vibrational dynamics of α-iron: the second neighbor distance exhibits anharmonicity and vibrational anisotropy larger than the first neighbor distance. We search for possible distortions of the bcc structure to justify the unexplained magnetostriction anomalies of α-iron and provide a value for the maximum dislocation of the central Fe atom.

Frequency analysis for modulation-enhanced powder diffraction.

Periodic modulation of external conditions on a crystalline sample with a consequent analysis of periodic diffraction response has been recently proposed as a tool to enhance experimental sensitivity for minor structural changes. Here the intensity distributions for both a linear and nonlinear structural response induced by a symmetric and periodic stimulus are analysed. The analysis is further extended for powder diffraction when an external perturbation changes not only the intensity of Bragg lines but also their positions.

A new multipurpose diffractometer PILATUS@SNBL.

The diffraction beamline BM01A at the European Synchrotron Radiation Facility (CRG Swiss-Norwegian beamlines) has been successfully operational for 20 years. Recently, a new multifunctional diffractometer based on the Dectris Pilatus 2M detector has been constructed, commissioned and offered to users. The diffractometer combines a fast and low-noise area detector, which can be tilted and moved horizontally and vertically, together with flexible goniometry for sample positioning and orientation.

Charge-ordering transition in iron oxide Fe4O5 involving competing dimer and trimer formation.

Phase transitions that occur in materials, driven, for instance, by changes in temperature or pressure, can dramatically change the materials' properties. Discovering new types of transitions and understanding their mechanisms is important not only from a fundamental perspective, but also for practical applications. Here we investigate a recently discovered Fe4O5 that adopts an orthorhombic CaFe3O5-type crystal structure that features linear chains of Fe ions.

Crystal structures of cristobalite-type and coesite-type PON redetermined on the basis of single-crystal X-ray diffraction data.

Hitherto, phospho-rus oxonitride (PON) could not be obtained in the form of single crystals and only powder diffraction experiments were feasible for structure studies. In the present work we have synthesized two polymorphs of phospho-rus oxonitride, cristobalite-type (cri-PON) and coesite-type (coe-PON), in the form of single crystals and reinvestigated their crystal structures by means of in house and synchrotron single-crystal X-ray diffraction. The crystal structures of cri-PON and coe-PON are built from PO2N2 tetra-hedral units, each with a statistical distribution of oxygen and nitro-gen atoms.

A composite of complex and chemical hydrides yields the first Al-based amidoborane with improved hydrogen storage properties.

The first Al-based amidoborane Na[Al(NH2 BH3 )4 ] was obtained through a mechanochemical treatment of the NaAlH4 -4 AB (AB=NH3 BH3 ) composite releasing 4.5 wt % of pure hydrogen. The same amidoborane was also produced upon heating the composite at 70 °C.

Crystal structure and thermal expansion of Mn(1-x)Fe(x)Ge.

A series of temperature-dependent single-crystal and powder diffraction experiments has been carried out using synchrotron radiation in order to characterize the monogermanides of Mn, Fe and their solid solutions. The MnGe single crystal is found to be enantiopure and we report the absolute structure determination. The thermal expansion, parametrized with the Debye model, is discussed from the temperature-dependent powder diffraction measurements for Mn(1-x)Fe(x)Ge (x = 0, 0.