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A new organic-inorganic hybrid [{p-(CH3)2NH—C6H4—NH3}2Cl][BiI6] was synthesized and its crystal structure was established. The hybrid consists of an inorganic anion [BiI6]3− and an organic cation [{p-(CH3)2NH-C6H4-NH3}2Cl]3+. The [BiI6]3− anions are linked via non-covalent I...I interactions between axial atoms of neighboring anions to form chains running along the c axis of the tetragonal unit cell. In the cationic part, the Cl− anion is involved in four (N)H…Cl hydrogen bonds with hydrogen atoms of the p-(CH3)2NH—C6H4—NH32+ cation, forming a two-dimensional substructure. Alternating covalent and I...I halogen bonds in the anionic substructure and cation—anion hydrogen bonds provide the formation of a three-dimensional supramolecular structure with a band gap of 1.93 eV.

Glycinium triiodide was synthesized and its crystal structure was determined. The crystal structure consists of alternating asymmetric triiodide anions characterized by Raman spectroscopy and glycinium cations. The cations and anions form dimers (GlyH)2(I3)2via (N)H···O, (N)H···I, and (O)H···I hydrogen bonds. The dimers are further linked into chains by secondary I···I interactions between adjacent triiodide anions. The supramolecular structure of glycinium triiodide is discussed in comparison with polyiodides of various cations.

Two new iodobismuthates with the composition LnBiI6•13H2O (Ln = La, Nd) were synthesized and their crystal structures were determined. The compound LaBiI6•13H2O crystalizes in the orthorhombic space group Pna21, a = 24.206(5), b = 8.405(1), c = 26.360(5) A; the compound NdBiI6•13H2O crystalizes in the monoclinic space group P21/n, a = 14.553(3), b = 13.386(3), c = 27.541(6) A, β = 92.80(3)°. In both crystal structures, the cations Ln(H2O)93+ and the anions BiI63– alternate, forming a NaCl-type structure, and the structures themselves differ in the arrangement of water of crystallization that leads to the formation of dissimilar systems of hydrogen bonds. Both compounds undergo decomposition when heated, which is accompanied first by a partial liberation of water molecule, followed by pyrohydrolysis to form oxoiodides LnOI as final solid products. According to optical measurements, the band gap of the obtained compounds was equal to 1.78 (La) and 1.71 (Nd) eV.

The solid solution Sn24AsxP19.3-xI8 in the range of compositions x from 0 to 16 was synthesized. The crystal structure was refined for seven compositions of the solid solution at —100 °C. All samples crystallize in the cubic space group Pm3 n with the unit cell parameters a = 10.9358(2)—11.1495(2) A and belong to the clathrate-I structure type. The distribution of the phosphorus and arsenic atoms over two independent crystallographic positions within the clathrate framework was analyzed. The difference in the structure of the substituted clathrates with the cationic and anionic clathrate frameworks is considered.

New double mercury silver phosphide iodide Hg12Ag41P88I41 (1) was synthesized and its crystal structure was established. Compound 1 crystallizes in the cubic system. The characteristic feature of the crystal structure 1 is the presence of the anionic cage clusters P113−, which have been previously found in alkali metal compounds only. The well-ordered P113− clusters form a system of polyhedra, which encapsulate various disordered α-AgI-type fragments.

New mixed bismuth monohalides Bi4BrxI4–x (x = 1, 2, or 3) were prepared for the first time by the reactions of bismuth metal with bismuth trihalides taken in stoichiometric amounts. Their crystal structures were established by single-crystal X-ray diffraction analysis. The Bi4Br3I and Bi4BrI3 compounds are isostructural and crystallize in the orthorhombic system, and Bi4Br2I2 crystallizes in the monoclinic system. The crystal structures of all three phases contain one-dimensionally infinite molecular chains consisting of the [Bi4X4] fragments whose structures are identical with those of the individual Bi4I4 and Bi4Br4 molecules. The molecules are packed in layers. Different packing modes of the layers were found for different bismuth monohalides. The Bi4ClI3 compound, which is apparently structurally similar to Bi4Br3I and Bi4BrI3, was also prepared.