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The electronic energy spectrum of the crystal and its sublattices of the crystalline a-phase of zinc chloride, the density of states, the total and deformation density of the charge distribution of valence electrons are calculated from the first principles using the density functional method. Optical vibrational modes are also calculated.

The work presents Raman spectra of platelike crystals of the CuCrS ₂ compound, which were grown from polycrystalline CuCrS ₂ by the CVD method with an elementary iodine as a carrier. The spectra are measured in the temperature range of 5-300 K. Observed vibrational modes are assigned based on the temperature dependences of their frequencies. In the temperature range of magnetic ordering ( Т < 40 K) a weak increase is observed in the frequencies of totally symmetric vibrations, which is interpreted as a result of the phonon-magnon interaction.

Elemental analyses, single crystal X-ray diffraction method, and ¹H and ¹³C NMR spectral techniques are used to synthesize and characterize the crystal structure of 4-diethylamino-2-{[4-(3-methyl-3-phenyl-cyclobutyl)-thiazol-2-yl]-hydrazonomethyl}-phenol. In order to calculate the molecular geometry along with vibrational frequencies and the gauge including atomic orbital (GIAO) ¹H and ¹³C NMR chemical shift values of the title crystal structure in the ground state, the Hartree-Fock (HF) and density functional theory (DFT) methods with 6-311G( d,p ) basis sets are utilized. The assignments of the vibrational frequencies are calculated with the help of the potential energy distribution (PED) analysis using the VEDA 4 software. Experimental data are used for comparison. The molecule contains C-H⋯O intra-inter-molecular interactions.

Ammonium dicobalt(II)-octa-molybdenum with the composition (NH ₄) ₂[Co(H ₂O) ₄] ₂[Mo ₈O ₂₇]×6H ₂O (I) is synthesized and studied by X-ray diffraction, IR spectroscopy, and thermogravimetry. The compound crystallizes in a triclinic system with the following unit cell parameters: a = 8.62923(9) Å, b = 9.4795(10) Å, c = 12.2071(13) Å, a = 104.326(2)°, b = 109.910(2)°, g = 100.820(2)°, V = 868.18(16) Å ³, ρ _(calc.) = 3.071 g/cm ³, Z = 1. Space group is Р -1. IR spectroscopic and thermogravimetric analyses are performed.

The complex of the composition [Pd ₂(H ₂L ¹)Cl ₄] (I) (H ₂L ¹ is a chiral bis-α-sulfanyl oxime, a derivative of natural monoterpenoid (+)-3-carene) is synthesized. Single crystals of I and solvate [Pd ₂(H ₂L ¹)Cl ₄]×0.5CH ₂Cl ₂ (II) are grown. According to the X-ray crystallographic data, the crystal structure of I consists of acentric molecules of the binuclear [Pd ₂(H ₂L ¹)Cl ₄] complex. The structure of solvate II consists of the molecules of binuclear complex I and CH ₂Cl ₂ molecules. The PdCl ₂NS coordination sites are distorted squares (trapezia). In the structures of I and II, the PdCl ₂ fragments are in the transoid position. In I, the Cl ₂NS planes of the two coordination sites are nearly parallel (the angle between the planes is 7.7(1)°). The similar angle in solvate II is 22.0(1)°.

Conditions are determined for the formation of sodium heteropolyhexamolybdenumnickelate(II) Na ₄[Ni(OH) ₆Мо ₆O ₁₈]·16H ₂O (I) in a Ni(NO ₃) ₂-Na ₂МоO ₄-HNO ₃-H ₂O solution acidified to Z = ν(H ⁺)/ν(МоO ) = 1.00. Synthesized salt I is investigated by chemical analysis, single crystal XRD, powder XRD, thermal analysis, and IR spectroscopy. The heteropolyanion is shown to belong to the Anderson type. Compound I is analyzed by single crystal XRD ( M _r = 1404.61, triclinic, space group P , a = 8.0586(4) Å, b = 10.5445(6) Å, c = 12.1374(5) Å, α= 69.557(5)Å, β = 70.604(4)Å, γ = 84.123(4)Å, V = 911.45(8) Å ³) to find that it is isostructural to Na ₄[Ni(OH) ₆W ₆O ₁₈]·16H ₂O. All metal atoms in the structure of I are in an octahedral environment: the coordination sphere of the Ni heteroatom consists of OH groups; that of Mo consists of O atoms and OH groups; Na atoms are linked to the heteropolyanion via the terminal O atoms of the polyanion and surrounded by water molecules. In the crystal packing, the [Ni(OH) ₆Mo ₆O ₁₈] ^4- anions lie in planes parallel to (1 0) and the polyanion layers alternate with those formed by the paired octahedra [Na ₂(μ-H ₂O) ₂(H ₂O) ₆(O) ₂] in the direction of the y axis.

The synthesis, crystal structures, and characterization (IR, TGA/DSC) of [Nd(C ₅H ₆O ₄)·(H ₂O) ₄]·Cl (1) and Pr(C ₅H ₆O ₄)(C ₅H ₇O ₄)(H ₂O)]·H ₂O (2) are described. Compound 1 is a one-dimensional coordination polymer containing double chains incorporating pairs of edge-sharing NdO ₉ polyhedra linked by glutarate dianions. A network of O-H⋯O and O-H⋯Cl hydrogen bonds helps to consolidate the structure. Compound 2 is a three-dimensional coordination polymer incorporating chains of edge-sharing PrO ₁₀ polyhedra. Its glutarate ion adopts an extended conformation, whereas its hydrogen glutarate ion takes on a twisted conformation. O-H⋯O hydrogen bonds are seen in the crystal structure, which features small channels occupied by water molecules. Crystal data: 1, C ₅H ₁₄ClNdO ₈, M _r = 381.85, monoclinic, P 2 ₁/ c (No. 14), a = 8.9763(6) Å, b = 15.9277(11) Å, c = 8.8690(6) Å, β = 112.090(2)°, V = 1174.94(14) Å ³, Z = 4, R ( F ) = 0.016, wR ( F ²) = 0.037. 2, C ₁₀H ₁₇O ₁₀Pr, M _r = 438.15, orthorhombic, Pbca (No. 61), a = 16.3030(7) Å, b = 8.6714(4) Å, c = 19.3899(8) Å, V = 2741.1(2) Å ³, Z = 8, R ( F ) = 0.020, wR ( F ²) = 0.050.

Branched star-like dextran-polyacrylamide copolymers in nonionic and ionic forms are used as matrices for the fabrication of silver nanoparticles. It is demonstrated that due to the features of their molecular structure providing a high local concentration of functional groups, branched polymers stabilize silver nanoparticles more efficiently as compared with their linear analogs. Stable silver colloids are obtained in a branched anionic matrix, meanwhile a linear matrix does not stabilize a nanosystem.

Quantum chemistry methods are used to analyze in detail the structure of the van der Waals complex of ethylene with oxygen C ₂H ₄-O ₂, and binding energies for stable configurations of the complex are calculated. The calculations are carried out by the MP2 method using the 6-311++G(2 d ,2 p ) and aug-cc-pV n Z ( n = 2, 3, 4) basis sets. It is demonstrated that the most stable structure of the van der Waals complex of ethylene with oxygen is a structure with C _{2 v} symmetry, where the oxygen and ethylene molecules are located parallel and lie in the same plane. The calculation of the binding energy for this structure using the aug-cc-pV n Z ( n = 2, 3, 4) basis sets with the extrapolation of results to the infinite basis set limit ( n → ∞) gives a value of 206 cm ^-1.

By alternating current electrochemical synthesis a new [Cu ₂( atfmphet ) ₂(CF ₃SO ₃) ₂] π complex is obtained from the alcohol solution of Cu(CF ₃SO ₃) ₂ and 5-(allylthio)-1-[2-(trifluoromethyl)phenyl]-1 H -tetrazole ( atfmphet ) and studied using single crystal X-ray diffraction.