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A Fourier IR spectroscopic study has shown that during injection solubilization of HCl solutions ( V _s/ V _o = 1.0-3.5 vol.%) at a concentration of 1-4 M by Triton N-42 reverse micelles in n -decane, the number of water molecules bound to protons is equal to 2.7±0.1. Protons form (70%) and (30%) cations in equilibrium, which are localized in the aqueous cores of the micelles.

The chlorobenzene (CB)- o -dichlorobenzene ( o -DCB) liquid system has been studied by classical molecular dynamics simulation over the entire range of concentrations. The structure of the solutions is characterized by using radial angular distribution functions for the distances between the planes of benzene rings and the angle between them, using radial distribution functions for the distances between chlorine atoms, and by calculating the self-diffusion coefficients and local dipole moments. Halogen aggregation in the pure components and solutions is analyzed. It is found that in pure CB, chlorine aggregates consisting of four to ten molecules are most likely to form. The sizes of chlorine aggregates increase with increasing o -DCB concentration, and at a o -DCB concentration of 0.50-1.00 ppm, an extended system of chlorine-chlorine contacts is formed. In pure o -DCB, the chlorine aggregation system includes 99% of the molecules of the simulated system. The agglomeration of solute molecules in the range of dilute solutions ( x < 0.1 ppm) is investigated.

Using the aggregation numbers of micelles and the effective sizes of hydrated surfactant ions and counterions of the first coordination sphere, we calculated the average geometric characteristics of the surface layer of ionic spherical micelles in solutions of the sodium n -alkyl sulfate homologues with n _C = 8, 10, 12, and 14 carbon atoms in the molecule; in particular, we established 1) the size of the micelle core; 2) the thickness of the electrical double layer on the surface; 3) the mutual arrangement parameters of hydrophilic and hydrophobic ions; 4) the number of “free” water molecules and showed their dependence on the homologue number and the degree of binding of counterions.

Crystal structures of newly synthesized tetramethylammonium hexafluoridoniobate(V) and hexafluoridotantalate(V) (CH₃)₄N[МF₆] (M=Nb, Ta) have been determined; they crystallize in the tetragonal crystal system, sp. gr. P 4/ nmm . Crystal structures of isostructural compounds (CH₃)₄N[МF₆] (M=Nb, Ta) are formed by virtually regular tetrahedral tetramethylammonium cations (CH₃)₄N⁺ (NMe₄, TMA) and octahedral complex anions [МF₆]^- (M=Nb, Ta), fluorine atoms of the equatorial plane are statistically disordered over two positions. Ionic interactions and weak hydrogen bonds C-H⋯F join the cations and the complex anions in a 3D assembly.

A complex compound [(NH₃)₆Rh₂(m-CO₃)(m-OH)₂](NO₃)₂×H₂O has been obtained and structurally characterized. Crystal data: a = 7.9103(16) Å, b = 9.606(2) Å, c = 11.283(2) Å, a = 103.206(4)°, b = 110.045(4)°, γ = 93.890(5)°, space group P -1, Z = 2, d _x = 2.335 g/cm³. The crystal structure is a packing of dimeric complex rhodium cations [Rh₂(m-OH)₂(m-CO₃)(NH₃)₆]²⁺, nitrate anions, and crystallization water molecules joined by a system of hydrogen bonds. The compound has been investigated with IR spectroscopy and powder X-ray diffraction. The isolated crystalline phase is poorly soluble in water.

A series of six-coordinated Ni(II) complexes, with the general formula Ni(Xan)L₂ (where Xan = isoamyldithiocarbonato and L = 2-bromopyridine, 3-bromopyridine, 4-acetylpyridine, 3-hydroxypyridine and 2-methoxypyridine) are synthesized and characterized by the elemental analysis and various physicochemical techniques such as magnetic susceptibility and conductivity measurements, UV-visible and infrared spectral data. Based on the electronic spectra and magnetic susceptibility measurements, an octahedral geometry is proposed for all the complexes. IR spectral data show that in all these complexes substituted pyridines coordinate to the metal ion through nitrogen atoms occupying the fifth and sixth axial positions, whereas O-alkyldithiocarbonate acts as a monoanion bidentate ligand and occupies the planar positions of octahedral structures. The structure of the adduct with 3-bromopyridine is elucidated by the single crystal X-ray diffraction method. The complex crystallizes in the triclinic space group P -1 with unit cell parameters a = 6.5855(4) Å, b = 9.4984(6) Å, c = 12.4518(8) Å, a = 87.944(5)°, b = 78.843(5)°, g = 77.794(5)°. The crystal structure of the molecule is stabilized by intermolecular C-H…S and C-H…p interactions.

Single crystal X-ray diffraction was applied for re-determination of the crystal structure of a- trans -[Pd(NH₃)₂Cl₂]. It has been demonstrated that, in contrast to the literature data, the structure is disordered. This model does not require excess over-stoichiometric palladium. Two crystals obtained in the same experiment illustrate possible variations in the packing of the molecules of the complex.

Double complex salts (DCS) a-[Pd(NH₃)₄][IrF₆]×H₂O ( P 2₁/ m , a = 6.3181(3) Å, b = 10.8718(5) Å, с = 7.4526(4) Å, b = 103.568(2)°), b-[Pd(NH₃)₄][IrF₆]×H₂O ( P 2₁/ с , a = 8.5773(3) Å, b = 10.8791(4) Å, с = 12.6741(3) Å, b = 122.497(2)°), [Pd(NH₃)₄]₃[IrF₆]₂Cl₂×H₂O ( P- 1, a = 7.6080(2) Å, b = 7.6274(2) Å, с = 11.8070(3) Å, b = 122.497(2)°), and [Pd(NH₃)₄]₂[IrF₆]NO₃ ( Fm -3 m , a = 11.21210(10) Å) have been synthesized and structurally characterized for the first time. The existence of polymorphs for the DCS has been revealed. The influence of the chemical composition of the initial reagents on the reaction course and, respectively, the products, has been demonstrated. A hypothesis on the influence of the second coordination sphere on the formation of one or the other polymorph of the DCS has been suggested. It has been shown that the series a-[Pd(NH₃)₄][МF₆]×H₂O (M = Pt, Pd) exhibits isostructurality.

A novel bimolecular crystal (BMC) of CL-20 and N,N'-dimethyl-N,N'-dinitrooxamide (MNO) has been prepared. Molecular and crystal structures have been determined. Thermal stability has been studied with DSC technique.

Indoline alkaloids kopsinilam and kopsinine extracted from the plant Vinca erecta have been studied by X-ray crystallography; mono and double salts of the latter alkaloid also have been examined. Experimentally determined positions of Н atoms suggest sp ³ hybridization of the indoline nitrogen atom N1 in the bases and the salts. Tetrahedral hybridization of the atom N1 in indoline alkaloids favors the formation of their double salts, what is unlikely for indole and indolinine alkaloids. In the halogen double salts there is an intramolecular Н bond between one of the protons of the NH₂ group and the oxygen of the methoxycarbonyl group, that is absent in the mono salts and pure bases.