Calculation of the optical spectra of the copper(I) complex with triphenylphosphine,iodine, and 3-pyridine-2-yl-5-phenyl-1<Emphasis Type="Italic">H</Emphasis>-1,2,4-triazole by the DFT method

The IR and UV spectra of the [CuIL(PPh₃)] complex (PPh₃ = triphenylphosphine, L = 3-pyridine- 2-yl-5-phenyl-1Н-1,2,4-triazole) have been analyzed in detail within the density functional theory (DFT) and its time-dependent version TD DFT. The standard functional B3LYP and sets of basis orbitals 6-311G(d,p) and Lanl2DZ are used for the atoms of the elements of periods I and II and for the iodine atom, respectively. The calculated IR spectra of the complex and free ligands coincide with the observed IR bands, due to which one can completely interpret all normal modes and confirm X-ray diffraction (XRD) data. Particular attention is paid to the structure of excited triplet (Т ₁) state in order to explain the role of copper and iodine ions in the formation of photo- and electroluminescence spectra. It is shown that the equilibrium Т ₁ state undergoes structural relaxation after the vertical excitation and significantly changes its electronic nature and the charge transfer structure.     

Application of the perturbation method in mechanics of deformable solids

Although the solutions of the classical problems of continuum mechanics have been studied sufficiently well, the smallest deviations, for example, of the body boundary or of the material characteristics from the traditional values prevent one from obtaining exact solutions of these problems. In this case, one has to use approximate methods, the most common of which is the perturbation method. The problems studied in [1–6] belong to classical problems in which the perturbation method is used to study the behavior of deformable bodies. A wide survey of studies analyzing the perturbations of the body boundary shape caused by variations in its stress-strain state is given in [5, 6]. In numerous studies, it was noted that the problem on the convergence of approximate solutions and hence the studies of the continuous dependence of the solution of the original problem on the characteristics of perturbations (“imperfections”) play an important role. In the present paper, we analyze the forms of mathematical models of deformable bodies by studying whether the solution of the original problem continuously depends on the characteristics of the perturbed shape of the body boundary on which the boundary conditions are posed in terms of stresses and on the characteristics of the material properties. We use the results of this analysis to conclude that, when using the perturbation method, one should state the boundary conditions in terms of stresses on the boundary of the real body in stressed state.     

Stabilizing hydrogen-hydrogen interactions in cationic indopolycarbocyanine dyes

A quantum chemical DFT method with the hybrid B3LYP functional in the 6-31G(d) basis set is employed to calculate the equilibrium geometric parameters of the ground and excited states of cationic symmetric indopolycarbocyanine dyes. Based on the Bader topological analysis of the electron density distribution function, it is found that there are hydrogen-hydrogen bonding interactions in the ground, first singlet, and first triplet states of the studied compounds. These interactions are assumed to have the dispersion character. The effect of the stabilization of the conformational position of methyl groups due to hydrogenhydrogen interatomic interactions on fluorescence deactivation processes is shown. The total stabilization energy of hydrogen-hydrogen interatomic interactions in dye cations is found, which is ≈9 kcal/mol.     

Quantum-chemical study of effect of conjugation on structure and spectral properties of C105 sensitizing dye

The structure and spectral properties of two organic ruthenium complexes used as sensitizing dyes for solar batteries (well-known N3 dye and its selenophene-conjugated analogue C105 ([Ru(bpy)(bpysef)(COOH)₂(NCS)₂] (bpy = 2,2′-bipyridine, bpysef = 4,4′-bis(5-hexylselenophene-2-yl)2,2′-bipyridine)) are comparatively studied within the density functional method. It is shown that the conjugation of the bipyridine ligand with selenophene affects the electronic structure of the C105 dye. A multilevel model for interpreting the electronic spectra of dyes is proposed based on the analysis of the shapes of molecular orbitals. The nature of the absorption bands of these ruthenium complexes in the region of 300–800 nm is explained. It is found that, in the polar acetonitrile solvent, these dyes are negatively solvatochromic, which agrees with the current classical views on the effect of the solvent on the shape of electronic absorption spectra of related compounds.     

Calcium peroxosilicates

Calcium peroxosilicates CaO·nSiO₂·xH₂O·yH₂O₂ (n = 1, 2) were synthesized by three methods: (1) the reaction of CaSiO₃·nH₂O (～7% CaSiO₃ suspension in water) with 50.7, 73.4, and 92% H₂O₂ at 0–5°C produced compositions CaSiO₃·6H₂O·2H₂O₂, CaSiO₃·2H₂O·4H₂O₂, and CaSiO₃·3H₂O·8H₂O₂, respectively; (2) the reaction of CaSiO₃·17H₂O with 50.7 and 73.4% H₂O₂ at 0–5°C produced the solvate CaO·2SiO₂·4H₂O·0.15H₂O₂; and (3) the reaction of CaSiO₃·3H₂O with H₂O₂ vapor at 5°C in the absence of anhydrone produced the solvate CaSiO₃·3.5H₂O·0.5H₂O₂. The products were characterized by X-ray powder diffraction, thermogravimetry, and IR spectroscopy.     

Synthesis of novel aminomethylenebisphosphonates and bisphosphonic acids,containing adamantyl fragment

Novel aminomethylenebisphosphonates containing an adamantyl fragment were synthesized by a solvent‐free, microwave‐assisted, three‐component reaction of amines, triethyl orthoformate, and O,O‐diethyl phosphite. Several bisphophonic acids were prepared from aminomethylenebisphosphonates by the treatment with trimethylsilyl bromide followed by methanolysis. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 22:55–58, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20656     

Theoretical study of the conformational structure and thermodynamic properties of 5-(4-oxo-1,3-thiazolidine-2-ylidene)-rhodanine and ethyl-5-(4-oxo-1,3-thiazolidine-2-ylidene)-rhodanine-3-acetic acid as acceptor groups of indoline dyes

The quantum chemical DFT method with the B3LYP hybrid functional in 6–31++G(d,p) and 6–311+G(d,p) basis sets is used to calculate the equilibrium geometric parameters of different conformations of 5-(4-oxo-1,3-thiazolidine-2-ylidene)-rhodanine and its substituted form ethyl–5-(4-oxo-1,3-thiazolidine-2-ylidene)-rhodanine-3′-acetic acid applied in the synthesis of indoline and some other sensitizing dyes for solar cells. The thermodynamic parameters of four conformers and their synthesis reactions are calculated. The effect of substituents on the thermodynamic stability of the studied isomers is shown.     

Synthesis and study of peroxotalc

Preparations of peroxotalc containing up to 6% O_act have been synthesized and studied by vibrational spectroscopy (IR, Raman), X-ray diffraction, and TGA. The stability of the compounds on storage and heating under iso- and polythermal conditions has been studied. The presence of peroxo groups was confirmed spectroscopically.