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The article reviews the current state of the chemistry of high-valence cluster compounds of group 3-7 transition metals containing interstitial heteroatoms. The synthesis methods, reactivity, main structural types, and electronic structure of resulting compounds are discussed.

N-(2-Hydroxyethyl)-β-alaninatonickel(II) was synthesized by the interaction of basic nickel carbonate with N-(2-hydroxyethyl)-β-alanine. The structures of the chelating agent and its nickel complex were studied by single crystal X-ray diffraction. In the synthesized compound, the nickel ion lies at the center of an octahedron of the N and 2O donor atoms of two tridentate ligands, each ligand having a meridional conformation. The ligands around the central atom are arranged in perpendicular planes. This coordination of two ligands yields two stereoisomers, whose cocrystallization affords a racemate.

Charge transfer complexes (CTCs) are obtained by the interaction of 9,10-phenanthrenequinone nitro derivatives with anthracene. By electron spectroscopy it is established that the acceptor properties of the former increase with increasing number of nitro groups and depend on their position. 1,3,6-Trinitro-9,10-phenanthrenequinone, which forms with anthracene a CTC with a charge transfer band near 658 nm, is found to be the strongest acceptor. Charge transfer values from the donor (D) to the acceptor (A), ranging from 0.034 ē to 0.091 ē, formation energies of [A–D] complexes, HOMO and LUMO gaps in CTC are found by quantum chemical calculations, and they correlate with the experimental positions of long-wave bands in the electron absorption spectra of the complexes in solutions. The crystal and molecular structures of new 1:1 CTC of 2,4,7-trinitro-9,10-phenanthrenequinone with anthracene is determined by single crystal X-ray diffraction. In crystal, CTC has a {⋯[A–D]⋯[A–D]′⋯}∞ packing of the mixed type where average interplanar distances are 3.35 Å, with the shortest C⋯C distance being 3.234(2) Å, and intermolecular C–H⋯O hydrogen bonds are in the range 2.50-2.69 Å.

Supramolecular, molecular and electronic structures of petroleum resins are studied. The experimental part includes isolation of resins by the eluent method and measuring electron and IR spectra. The structural parameters are calculated by molecular mechanics and DFT/B3LYP methods. The calculated data are in good agreement with the experiment. The nonplanar structure of petroleum resins is confirmed by the results of our structural study.

The compressibility of γ-K2CO3 within the pressure range of 0.001-23.3 kbar and room temperature was determined by in situ synchrotron powder diffraction measurements in diamond anvil cell. The modification of the diffraction pattern was fixed at P > 23.3 kbar. This modification can be explained by a reconstructive phase transition. The amorphization of the high pressure phase was fixed on decompression.

A comprehensive study of the electronic structure of trinuclear molybdenum complexes (NH4)2[Mo3S13] and [Mo3S7(dtc)3]Br with cluster core {Mo3S7} and [Mo3S4(tu)8H2O]Cl4 complexes with cluster core {Mo3S4} is conducted by X-ray emission spectroscopy (XES), X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) spectroscopy, and quantum chemistry methods. Data were obtained on the partial atomic composition of the highest occupied molecular orbitals and unoccupied molecular orbitals and the nature of atomic interactions within cluster cores.