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Single crystals of the perovskite nickelate NdNiO3 with dimensions of up to 50 μm on edge have been successfully grown using the flux method at a temperature of 400 °C and oxygen pressure of 200 bar. The crystals were investigated by a combination of techniques, including high-resolution synchrotron X-ray single-crystal and powder diffraction and physical property measurements such as magnetic susceptibility and resistivity. Resistivity measurements revealed a metal-insulator transition (MIT) at TMIT~180 K with apparent thermal hysteresis; however, no superlattice peaks or peak splitting below TMIT, which corresponds to a structural transition from Pbnm to P21/n, was observed. The successful growth of NdNiO3 crystals at relatively low temperatures and oxygen pressure provides an alternative approach for preparing single crystals of interesting perovskites such as RNiO3 (R = Sm-Lu) and parent phases of superconducting square planar nickelates.

High occupancy of cation sites is typical for clathrate-I compositions allowing limited tunability of the electrical properties beyond doping and elemental substitution. Herein, we report on the structure and electrical transport of single-crystal Eu 2 Ga 11 Sn 35 , the sole example of a very low (25%) cation concentration clathrate-I material with atypical transport directly attributable to the structure and stoichiometry.

We report the synthesis and oxygen-atom transfer (OAT) photochemistry of [Cu(tpa)BrO 3 ]ClO 4 . In situ spectroscopy and in crystallo experiments indicate OAT proceeds from a Cu–O fragment generated by sequential Cu–O bond cleavage and OAT from BrO x to [Cu(tpa)] + . These results highlight synthetic opportunities in M–O photochemistry and demonstrate the utility of in crystallo experiments to evaluating photochemical reaction mechanisms.

Single crystals of a new ternary chalcogenide Cu3InSe4 were obtained by induction melting, allowing for a complete investigation of the crystal structure by employing high-resolution single-crystal synchrotron X-ray diffraction. Cu3InSe4 crystallizes in a cubic structure, space group P4¯3m, with lattice constant 5.7504(2) Å and a density of 5.426 g/cm3. There are three unique crystallographic sites in the unit cell, with each cation bonded to four Se atoms in a tetrahedral geometry. Electron localization function calculations were employed in investigating the chemical bonding nature and first-principle electronic structure calculations are also presented. The results are discussed in light of the ongoing interest in exploring the structural and electronic properties of new chalcogenide materials.

The separation of xylene isomers still remains an industrially challenging task. Here, porous purine-based metal–organic frameworks (MOFs) have been synthesized and studied for their potential in xylene separations. In particular, Zn(purine)I showed excellent para -xylene/ ortho -xylene separation capability with a diffusion selectivity of 6 and high equilibrium adsorption selectivity as indicated by coadsorption experiments. This high selectivity is attributed to the shape and size of the channel aperture within the rigid framework of Zn(purine)I.