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For the first time, hybrid organic-inorganic 4-amino-1,2,4-triazolium fluorohafnate of the composition (C₂H₅N₄)[HfF₅(H₂O)₂]×H₂O is synthesized and its crystal structure is determined. The formation of a new type of a fluoride monomeric pentagonal bipyramid complex [HfF₅(H₂O)₂]^– anion with five F atoms and two H₂O molecules is revealed.

By X‑ray diffraction study the structure of two new carbonyl cluster complexes of the composition [Fe₄(μ₄-Q)(μ₄-AsMe)(CO)₁₁], where Q = Se or Te, is determined. The structures are molecular, and the selenium-containing cluster complex crystallizes in the form of a solvate with toluene.

By the interaction between (Et₄N)₂[Mo₂O₂S₈] and I₂ in DMF with a subsequent addition of 2,2'-bipyridine or 1,10-phenanthroline, new binuclear complexes [Mo₂O₂S₂I ₂(bipy)₂] (1) and [Mo₂O₂S₂I₂(phen)₂] (2) are obtained. The structure of [Mo₂O₂S₂I₂(bipy)₂] is determined using single crystal X‑ray diffraction. The compounds are characterized by elemental analysis and IR spectra. The [MoO(S₂)₂(bipy)] complex as a product of oxidative destruction of 1 is isolated and characterized.

Complex rhodium(III) salts of the composition cis-M[Rh(NH₃)₂(NO₂)₄]×n H₂O, where M = K⁺, Cs⁺, Ag⁺, (CH₃)₄N⁺, are synthesized and described. Their molecular and crystal structures are determined by single crystal X‑ray diffraction.

In this study four coordinated complexes of zinc(II) halides with a new symmetrical bidentate Schiff base ligand (2,5-MeO-ba)₂En are synthesized and characterized. The metal to ligand ratio of the complexes is found to be 1:1 with the formula of Zn((2,5-MeO-ba)₂En)X₂ (X = Cl (1), Br (2), I (3)). The crystal structure of the Schiff base ligand (2,5-MeO-ba)₂En is determined by X-ray crystallography from single crystal data. Also, the optimized geometries of the Schiff base ligand (2,5-MeO-ba)₂En and its zinc(II) complexes are calculated using the density functional theory method (B3LYP/6-31g). The obtained structural parameters of (2,5-MeO-ba)₂En are in agreement with the experimental data.

The Schiff base compounds N,N'-bis(3,4-dimethoxybenzylidene)-2,2-dimethylpropane-1,3-diamine hydrate, (3,4-MeO-ba) ₂Mepn.H₂O (1), and N,N'-bis(3,4-dimethoxybenzylidene)butane-1,4-diamine, (3,4-MeO-ba)₂bn (2), with different central groups derived from 3,4-dimethoxybenzaldehyde are synthesized and characterized by elemental analysis, FT—IR and ¹H NMR spectroscopy. The crystal structure of 1 is determined by single crystal X-ray diffraction. Each imino functional group (—C=N—) is coplanar with its adjacent benzene ring and the two benzene rings form a dihedral angle of 86.868(27)°. Title compound 1 crystallizes in the monoclinic space group P2₁/n with unit cell parameters: a = 9.0774(2) Å, b = 29.2138(5) Å, c = 8.5696(2) Å, b = 92.4756(14)°, V = 2270.41(8) ų and Z = 4.

Two 4-phenylbenzophenones (I) and (II) are synthesized via Friedel—Crafts reactions. There are four crystallographically independent molecules with different conformations in the crystal structure of [1,1'-biphenyl]-4-yl(2-chlorophenyl)methanone (I). Crystals are orthorhombic, Pca2₁, C₁₉H₁₃ClO, a = 13.699(3) Å, b = 8.9385(17) Å, c = 46.836(9) Å; V = 5735(2) ų, Z = 16, dx = 1.356 g/cm³. Torsion angles between the biphenyl rings are between 28.5° and 30.8°. Several C—H…O and C—H…Cl hydrogen bonds and weak π—π stacking contacts consolidate the crystal. Crystals of [1,1'-biphenyl]-4-yl(3-methoxyphenyl)methanone (II) are orthorhombic, Pbca, C₂₀H₁₆O₂, a = 7.8179(15) Å, b = 16.003(3) Å, c = 23.345(5) Å; V = 2920.7(10) ų, Z = 8, dx = 1.311 g/cm³. The torsion angle between the biphenyl rings is 28.1° and C—H…O hydrogen bonds are observed in compound (II).

The reaction of cadmium(II) chloride and 4-pyridine carboxylic acid (4-Hpyc) produces a new three-dimensional supramolecular compound [Cd(4-pyc)₂(H₂O)₄]_n (1). Compound 1 is characterized by IR spectroscopy and elemental analyses. The single crystal X-ray data show an infinite three-dimensional structure formed by the hydrogen bonding and π—π stacking interactions. The CdO nanoparticles are obtained by direct calcination at 400 °C, 500 °C and 600 °C in the air atmosphere as well as by thermolysis in oleic acid at 200 °C. The obtained cadmium(II) oxide nanoparticles are characterized by X-ray diffraction and scanning electron microscopy. This study demonstrates another potential application of cadmium(II) supramolecular compounds in the preparation of nanoscale cadmium(II) oxide materials with a specific size and morphologies.

A method to predict the vaporization enthalpies of aldehydes and ketones of different structures under normal conditions is proposed based on the modified Randič method.

Partial volumes V⁰ of amino acids in aqueous NH₄Cl and NaCl solutions are discussed. The salts have different effects on water structure. The contributions of the charged NH₃⁺ and COO^– groups of amino acids are found. Structural characteristics of hydrated complexes are calculated: partial volumes of water inside and outside the hydration sphere and hydration numbers. The same value of V⁰(NH₃⁺, COO^–) is achieved at a higher NH₄Cl concentration. The two salt systems with the same V⁰(NH₃⁺, COO^–) have similar values of the partial volumes of water and hydration numbers.