Front Cover: Steric Influence on the Constitution of Beryllium Phosphine Complexes (Eur. J. Inorg. Chem. 29/2023)

The phosphine complexes of beryllium chloride, bromide and iodide, [(PMe₂Ph)₂BeX₂], [(PMePh₂)₂BeX₂] and [(PPh₃)BeX₂]₂ (X=Cl, Br, I) were prepared and characterised with multinuclear NMR spectroscopy. Additionally the molecular structure of dinuclear [(PPh₃)BeCl₂]₂ was determined with single crystal X-ray diffraction techniques. The threshold cone angle of the phosphines, below which two ligands can coordinate to the beryllium dihalide fragments, is between 136° and 145°. Halide-chloride exchange in dichloromethane is observed for [(PPh₃)BeBr₂]₂ and [(PPh₃)BeI₂]₂, which leads to the formation of [(PPh₃)BeCl₂]₂. Due to the relatively low Lewis basicity of PPh₃, it almost exclusively acts as a spectator ligand with only little formation of phosphonium cations.     

Simulation of phase transitions induced in gallium arsenide by combined laser radiation

We performed a numerical simulation of phase transitions in gallium arsenide that are induced by the combined action of nanosecond laser pulses initiating melting and an additional neodymium-glass laser irradiation enabling the control of the interface velocity. In the case of counterpropagating laser beams, a strong temperature dependence of the absorption factor at 1.06 μm occurs. It causes a thermal wave, which separates from the melting front and, propagating towards the neodymium-glass laser beam, screens the melt. For copropagating laser beams, regimes with a nonmonotonic time dependence of the melt depth may exist.     

Binary Lead Fluoride Pb3F8

The binary lead fluoride Pb₃F₈ was synthesized by the reaction of anhydrous HF with Pb₃O₄ or by the reaction of BrF₃ with PbF₂. The compound was characterized by single-crystal and powder X-ray diffraction, IR, Raman, and solid-state MAS ¹⁹F NMR spectroscopy, as well as thermogravimetric analysis, XP and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Solid-state quantum-chemical calculations are provided for the vibrational analyses and band assignments. The electronic band structure offers an inside view of the mixed valence compound.     

Topology of hydrogen-bonded clusters in sub- and supercritical <Emphasis Type="Italic">n</Emphasis>-buthanol. Molecular dynamics simulation

We present the study of hydrogen-bonded clusters in sub- and supercritical n-buthanol by molecular dynamics. A number of characteristics of hydrogen bonds were calculated on the basis of a geometrical criterion. It was determined that the effect of the partial reduction of the structure of condensed medium near critical point is manifested in an increase in the average number of hydrogen bonds and the first peak of the hydrogen-oxygen radial distribution function. By investigating the topology of hydrogen-bonded clusters, it was shown that this reduction is determined by an increase of the fraction of molecules bound by two hydrogen bonds, and a reduction in the fraction of unbonded ones.     

Formation of the Active Surface of the FeCrAl Catalyst under Electric Current Heating Conditions

Russian Journal of Applied Chemistry - An effect of heat treatment conditions (convective, resistive heating) was considered on the composition and surface properties of FeCrAl wire used as a...     

Equilibrium and Non‐Equilibrium Melting of Two‐Dimensional Plasma Crystals

Recent progress in experimental and theoretical studies of melting of two‐dimensional (2D) plasma crystals is summarized. Several generic, equilibrium and non‐equilibrium processes which can be observed and investigated in 2D complex plasmas are discussed, such as KTHNY, grain‐boundary‐induced, and shear‐induced melting. Furthermore, the key features of the dominant plasma‐specific mechanism of melting operating in 2D plasma crystals, the mode‐coupling instability, are presented. The onset of the instability, which is characterized by threshold values of the experimental parameters, identifies the “dividing line” between the regimes when 2D complex plasmas can be employed to study generic strong‐coupling phenomena, and the situations when the melting occurs due to specific processes peculiar to complex plasmas. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

RbBrF4 Revisited

Rubidium tetrafluoridobromate(III) was synthesized and structurally characterized. The compound is isotypic to sodium and potassium tetrafluoridobromate(III), and crystallizes in the tetragonal space group I4/mcm (tI24, KBrF₄ structure type) with a = 6.3718(2), c = 11.4934(3) Å, V = 466.63(2) ų, Z = 4, at T = 293 K. Additionally we investigated the compound by means of IR and Raman spectroscopy as well as theoretical studies. The data obtained by quantum chemical calculations confirm the crystal structure, and also the atomic distances and angles with an average deviation of 2.2 to 2.7 %.