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The radial distribution of hydrogen on C_20(cage) and C₁₉Si_(cage), and C₁₉B_(cage) fullerene structures is investigated at different temperatures (273, 293, 320, and 400 K) for the pressure range between 1 MPa and 30 MPa using the (N,V,T) Monte Carlo simulation. The gravimetric storage capacity and radial distribution function parameters show that, under the identical temperature and pressure conditions, the magnitude of the hydrogen radial distribution on the C₁₉B surface is larger than that on C₁₉Si and C₂₀. The calculated maximum of the gravimetric storage capacity for C₁₉B at 273 K and 30 MPa is 7.6 %.

A procedure of the X-ray diffraction study of thin layers using a single crystal X-ray diffractometer equipped with a microfocus tube is described. It is demonstrated that a-cobalt phthalocyanine layers deposited by thermal vacuum evaporation onto polished surfaces of substrates (glass, quartz) have a perfectly oriented polycrystalline structure. The (00 l ) planes of all crystallites are oriented along the surface of the substrate. The structural organization of layers is analyzed.

The structure of 5,7-di( tert -butyl)-2-(6,8-dimethyl-4-chloroquinoline-2-yl)-3-hydroxytropone with a hydrogen atom, possibly equally distributed over two N and O centers and involved in the intramolecular hydrogen bond, is determined by the single crystal X-ray diffraction analysis.

The structure of [Pb₃(OH)₄Co(NO₂)₃](NO₃)(NO₂)×2H₂O is determined by single crystal X-ray diffraction. The crystallographic characteristics are as follows: a = 8.9414(4) Å, b = 14.5330(5) Å, c = 24.9383(9) Å, V = 3240.6(2) ų, space group Pbca , Z = 8. The Co(III) atoms have a slightly distorted octahedral coordination formed by three nitrogen atoms belonging to nitro groups (Co-N_av is 1.91 Å) and three oxygen atoms belonging to hydroxyl groups (Co-O_av is 1.93 Å). The hydroxyl groups act as m₃-bridges between the metal atoms. The geometric characteristics are analyzed and the packing motif is determined.

A novel form of anhydrous dicalcium phosphate CaHPO₄ (monetite) is synthesized hydrothermally and characterized by single crystal X-ray diffraction. It crystallizes in the orthorhombic space group Ccm 2₁ with a = 6.242(1) Å, b = 6.994(2) Å, c = 7.003(3) Å, V = 305.73(16) ų and it has four independent unit formulas in the unit cell ( Z = 4). A three-dimensional crystal structure can be described by {HPO₄} _n infinite zigzag chains linked by Ca-O bonds. The comparison to the crystal structures of other polymorphs is given.

Single crystals of 1-cyclohexylpiperazine-1,4-diium dichromate(VI), (C₁₀H₂₂N₂)[Cr₂O₇], were obtained by slow evaporation at room temperature from an aqueous solution of potassium dichromate, hydrochloric acid and 1-cyclohexylpiperazine. (C₁₀H₂₂N₂)[Cr₂O₇] is triclinic ( P ) with a = 10.351(2) Å, b = 12.766(3) Å, c = 6.111(1) Å, a = 91.50(2)°, b = 104.26(3)°, g = 94.91(2)°, V = 778.8(3) ų, and Z = 2. The structure determination performed from single crystal X-ray diffraction data leads to R ₁/ wR ₂ reliability factors of 0.032/0.078. The asymmetric unit of the title salt consists of one 1-cyclohexylpiperazine-1,4-diium dication and one dichromate dianion. These entities are linked together by N-H⋯O hydrogen bonds to form {(C₁₀H₂₂N₂)[Cr₂O₇]} _n infinite chains lying parallel to the (100) plane and running along the c axis. The intermolecular N-H⋯O hydrogen bonds link these chains into a two-dimensional network structure consolidated through C-H⋯O weak interactions.

The atomic structure of the higher molecular orbitals (MO) of small tetra-heme cytochrome (STC) with 1M1P is studied in large non-empirical calculations performed by the Hartree-Fock method with taking into account all electrons. It is shown that the higher MO of STC are mainly formed by atomic orbitals of negatively charged amino acid atoms. The corresponding amino acids and their numbers are determined. The conclusion is drawn that these amino acids can be considered as possible active centers in the electron transfer reaction from STC to the external electron acceptor.

By the DFT method with the planar wave basis set and in the PAW approximation the geometric and electronic structures of four supramolecular compounds of porphyrin and fullerene molecules in the crystalline state are performed: H₂TPPxC₆₀x3 toluene, H₂T_pivPPxC₆₀, H₂T_3,5-dimethylPPxC₇₀x4 toluene, and NiT_4-methylPPx2C₇₀x2 toluene. The geometry is optimized using the PBE functional and the Grimme DFT-D2 dispersion interaction correction. The electronic structure and absorbance spectra are calculated using the HSE functional. It is shown that the Показано, the H₂TPPxC₆₀x3 toluene structure having a sufficiently wide absorbance wavelength range, which results in a photoinduced electron transition from the higher occupied states formed by porphyrin molecules to the lower unoccupied states formed by fullerene molecules, are most promising for the design of photogalvanic elements.

The structure and electric properties of open carbon nanotube chirality (4,4), consisting of 5-15 segments, are calculated within four quantum chemical models: AM1, PM3, LSDA/3-21G*, and B3LYP/6-31G. Size effects and the effect of the model choice on the geometry, energy, enthalpy and Gibbs energy of the formation (atomization), Mulliken atomic charges, polarizability, and predicted adsorption properties of nanotubes are discussed.

Compound (⁷Li, ¹H) NMR and impedance spectroscopy methods are used to study the ion mobility and conductivity in a complex of the composition Li(NH₃CH₂COO)(NO₃) (I), which has a layered crystal structure. The character of ion motions in lithium and proton sublattices with temperature variation is considered; the types of motions and temperature ranges in which they occur are determined. It is found that above 350 K the dominant process in the lithium sublattice of the compound is Li⁺ ion diffusion. Possible migration paths of lithium ions in the lattice of the compound are analyzed. The conductivity of the compound is found to be 2.4x10^-6 S/cm at 393 K.