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Journal of Structural Chemistry

2009 year, number 2

1.
AB INITIO QUANTUM-CHEMICAL CALCULATIONS OF THE ENERGIES AND STRUCTURES OF 1,2-ACETYLENEDITHIOL ISOMERS

Y. V. Frolov, A. V. Vashchenko, A. G. Mal'kina, B. A. Trofimov
Keywords: ab initio quantum-chemical calculations, 1,2-acetylenedithiol, 1,2-dithiet, 1,2-dithioglyoxal, aromaticity
Pages: 211-215

Abstract >>
Ab initio quantum-chemical calculations of 1,2-acetylenedithiol isomers were carried out. The MP2(full), DFT(B3PW91, MPW1PW91), G3, G3B3, and CBS-Q methods were used. According to the calculations, the most stable isomers were 1,2-dithiet, thiiranethione, and trans-1,2-dithioglyoxal. The necessity of including basis set functions with a large angular momentum in calculations was confirmed. The relatively high stability of 1,2-dithiet was attributed to the aromaticity of its four-membered ring. It was noted that the carbon-carbon bond in the three-membered rings of the cis- and trans-isomers of thiirenethiols was unusually short.



2.
THEORETICAL STUDIES OF THE STRUCTURE OF NITRIMINES. I. STRUCTURE OF 2-NITROGUANIDINE AND ITS ALKYL DERIVATIVES

A. M. Astakhov, K. P. Dyugaev, A. A. Kuzubov, V. A. Nasluzov, A. D. Vasiliev, É. S. Buka
Keywords: energetic compounds, nitrimines, nitroguanidine, molecular structure, bond lengths, bond angles, quantum-chemical calculations
Pages: 216-226

Abstract >>
The molecular structure of 2-nitroguanidine and its 1-methyl, 1-ethyl, and 1,1,3,3-tetramethyl derivatives was studied by quantum-chemical methods. The results were compared with X-ray data. Using a basis larger than 6-31G and polarization functions and including electron correlation in calculations did not improve agreement with experiment. The major reason for this is the considerable effect of the crystal field on the geometrical parameters of the molecules.



3.
NITROSONIUM NITRITE ISOMER OF N2O3: QUANTUM-CHEMICAL DATA

I. I. Zakharov, O. I. Zakharova
Keywords: density functional method, quantum-chemical calculations, dinitrogen trioxide, isomers, nitrosonium nitrite
Pages: 227-234

Abstract >>
The geometrical, electronic, and thermodynamic parameters of three known isomers of dinitrogen trioxide N2O3 were calculated by the density functional theory DFT/B3LYP method using the 6-311++G(3df) basis. The structure of the new isomer, NONO2, was calculated. From the calculation of vibrational frequencies it follows that the structure of NONO2 has a local potential energy minimum and corresponds to the stationary state of the N2O3 isomer. The molecular structure of NONO2 is characterized by a substantial negative charge on the NO2 fragment and positive charge on the NO fragment. The electronic structure of the isomer can be characterized as nitrosonium nitrite, which can be oxidized to nitrite and participate in nitrosylation in accordance with the biogenic characteristics of the NOx intermediate, assumed to be formed in biological systems during the oxidation of NO.



4.
VIBRATIONAL DYNAMICS OF Co67Zr33 SEMICONDUCTOR GLASSY ALLOY

A.M. Vora
Keywords: Co, Zr, pair potential, semiconductor glassy alloy, phonon dispersion curves (PDC), thermodynamic properties, elastic properties
Pages: 235-242

Abstract >>
The computation of vibrational dynamics of semiconductor Co67Zr33 glassy alloy has been reported for the first time that uses a different theoretical model potential formalism with Wills-Harrison (WH) form. Various local field correction functions are used to study the screening influence. The thermodynamic and elastic properties are also estimated from the elastic limits of the phonon dispersion curves (PDC). The dispersion frequency with respect to the wavenumber is found to be influenced by the dielectric screening due to the conduction electrons. Values obtained using the S-local field correction function and BS approach tend to be greater than other values calculated.



5.
MOLECULAR STRUCTURE OF LuBr3 ACCORDING TO THE DATA OF THE SIMULTANEOUS ELECTRON DIFFRACTION AND MASS SPECTROMETRIC EXPERIMENT

N. I. Giricheva, S. A. Shlykov, G. V. Girichev, Ye. V. Chernova, Ye. A. Lapykina
Keywords: gas-phase electron diffraction, mass spectrometry, lutetium tribromide, molecular structure, vibration frequencies
Pages: 243-250

Abstract >>
The saturated vapor of lutetium tribromide was studied in the simultaneous electron diffraction and mass spectrometric experiment at 1161(10) K. Along with the monomer molecular forms, the vapor contained an insignificant (up to 3 mol.%) amount of dimers. The parameters of the effective configuration of the monomer molecule were determined. The internuclear distance rg(Lu-Br) is 2.553(5) Å, and the effective bond angle ∠g(Br-Lu-Br) is 115.3(10)°. The temperature-averaged rg parameters were calculated by the B3LYP method using the potential functions obtained by scanning the PES along the vibration coordinates and compared with similar experimental values. It was shown that the geometrical model of the LuBr3 molecule of D3h symmetry was consistent with the experimental data. The dependence of the rg parameters of the LuBr3 molecule on the vapor temperature was studied theoretically.



6.
MOLECULAR STRUCTURE OF ErCl3 AND YbCl3 ACCORDING TO THE DATA OF THE SIMULTANEOUS ELECTRON DIFFRACTION AND MASS SPECTROMETRIC EXPERIMENT

N. I. Giricheva, S. A. Shlykov, G. V. Girichev, E. V. Chernova, E. A. Lapykina
Keywords: gas-phase electron diffractometry, mass spectrometry, erbium trichloride, ytterbium trichloride, vapor composition, molecular structure, vibration frequencies, quantum-chemical calculations, anharmonicity of vibrations
Pages: 251-261

Abstract >>
The saturated vapors of ErCl3 and YbCl3 were studied in a simultaneous electron diffraction and mass spectrometric experiment at 1165 K and 1170 K, respectively. In the vapors of these compounds, we found up to 3 mol.% dimers along with the monomers. The parameters of the rg effective configuration of the monomer molecules were determined. For ErCl3 and YbCl3, the internuclear distances rg(Ln-Cl) were 2.436(5) Å and 2.416(5) Å, and the bond angles ∠g(Cl-Ln-Cl) were 117.0(10)° and 117.2(10)°, respectively. The equilibrium configurations and vibration frequencies of the monomer and dimer molecules were calculated by the HF, B3LYP, and ÌÐ2 methods using the combination of the ECPD energy-consistent quasirelativistic core potential, including 4f electrons [Kr4d104fn], and the contracted [5s4p3d] valence basis set for Er and Yb atoms and the MIDIX [4s3p1d] basis set for Cl atoms. The parameters of the effective rg configuration of the monomer molecules corresponding to the temperature of the experiment were calculated. The difference between the calculated equilibrium rå(Ln-Cl) and temperature-averaged rg(Ln-Cl) distances was found to be 0.001-0.002 Å and did not exceed the error of the rg(Ln-Cl) parameter determined in the electron diffraction experiment. The experimental parameters of the rg structure were shown to be consistent with the idea about the planar equilibrium geometrical configuration of ErCl3 and YbCl3 molecules.



7.
IR-FOURIER SPECTROSCOPIC STUDY OF HOMOGENEOUS AND HETEROPHASE MELTS AND GLASSES IN THE K,Ca/NO3 SYSTEM

M. M. Gafurov, K. S. Rabadanov
Keywords: infrared spectra, nitrate glasses, filled systems
Pages: 262-266

Abstract >>
The infrared spectra of the homogeneous and heterophase melts and glasses of the K,Ca/NO3 system were studied. The effects of finely disperse Al2O3 powder additions on the structural dynamic properties of K,Ca/NO3 were revealed. The temperature dependence of the parameters of the vibration bands corresponding to the inner vibrations of was studied. A model of structure and a mechanism of charge transfer in heterophase nitrate glasses were suggested.



8.
THERMODYNAMIC ACTIVATION PARAMETERS OF HINDERED ROTATION OF THE CF3 GROUP IN THE 4-NITROPHENYLTRIFLUOROMETHYLSULFONE RADICAL ANION IN DMF

L. A. Shundrin, E. A. Polenov
Keywords: sulfones, radical anions, hindered rotation, EPR spectroscopy, U-B3LYP
Pages: 267-274

Abstract >>
The thermodynamic activation parameters of hindered rotation of the CF3 group in the 4-nitrophenyltrifluoromethylsulfone radical anion in DMF were determined from the temperature dependence of the EPR line widths and spin density distributions calculated by the U-B3LYP method in the 6-31+G* basis set. In the range 293 > T > 199 K, the activation energy of hindered rotation EF depends on the temperature and changes in the range 9.67 < EF < 18.95 kJ·mol-1; the changes in the activation enthalpy and entropy are 7.23 < ΔH < 17.30 kJ·mol-1 and −53.45 < ΔS < -11.37 J·(mol·K)-1, respectively. Based on the suggested method for evaluating the inner product of the g tensor and the tensor of anisotropic hfi with the 14N nucleus for nitrobenzene radical anions in the liquid state we calculated the correlation time and determined the activation energy of rotational diffusion of the 4-nitrophenyltrifluoromethylsulfone radical anion in DMF, Er = 20.175±0.54 kJ·mol−1.



9.
DETERMINATION OF THE PARAMETERS OF ATOMIC PAIR CORRELATIONS IN NICKEL OXIDE FILMS BY THE ELECTRON ENERGY LOSS FINE STRUCTURE METHOD

D. E. Guy, O. R. Bakieva, A. N. Deev, F. Z. Gilmutdinov
Keywords: electronic spectroscopy, electron energy loss spectra, atomic pair correlation function
Pages: 275-282

Abstract >>
The electron energy loss extended fine structure (EELFS) spectra were obtained from the pure nickel surface (M2,3 EELFS) of a stoichiometric NiO film (NiM2,3 and OK EELFS spectra) and the "nonhomogeneous" oxide film on the surface of nickel Ni-O (NiM2,3 and OK EELFS spectra). The amplitudes and intensities of electron transitions for the core levels of atoms were calculated with regard for the multiplicity of electron impact excitation of the corresponding core levels of atoms. The corresponding normalized oscillating terms were isolated using the results of calculations based on the experimental EELFS spectra. Agreement between the experimental and calculated (on Ni and NiO test objects) data showed that the theoretical approaches used and the calculated data for describing the EELFS spectra are good approximations. Using the results of calculations and the parameters of secondary electron elastic scattering (FEEF-8 data) we obtained the atomic pair correlation functions from the experimental normalized oscillating parts of the EELFS spectra by Tikhonov's regularization method.



10.
RUTHENIUM−CARBON NANOCOMPOSITE

N. B. Shitova, P. G. Tsyrulnikov, D. A. Shlyapin, P. S. Barbashova, D. I. Kochubei, V. I. Zaikovskii
Keywords: ruthenium, complexes, pyrolysis, composite, nanoparticles
Pages: 283-287

Abstract >>
TEM, XRPA, and EXAFS studies showed that pyrolysis of [Ru(dipy)3](Cl)2 formed planar, two-dimensional, nanoparticles of ruthenium metal, stabilized in the carbon matrix.



11.
PROTON ADSORPTION AND ACID-BASE PROPERTIES OF TUNISIAN ILLITES IN AQUEOUS SOLUTION

A. Kriaa, N. Hamdi, E. Srasra
Keywords: minerals, clays, illite, point of zero charge, potentiometric titration, surface ionization constants
Pages: 288-301

Abstract >>
Suspensions of illite clay minerals samples of three different origins (American illite from Montana, It(Mo), Tunisian glauconite from Gafsa, It(Ga), and Tunisian illite - chlorite mixed layer from El Hamma, It(Ha)) were prepared. The Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffractometry (XRD), Electron Scanning Microscopy (SEM) and surface area measurements were used to characterize the three illite samples having different extent of isomorphic substitution. The layers have a permanent negative charge due to isomorphic substitutions and pH dependent charges on the surface hydroxyls on the edges. Surface speciation of these samples was investigated using continuous potentiometric titration and mass titration curves between pH 4 and 11 at 0.001, 0.01 and 0.1 M NaCl solutions at ambient temperature. The two methods revealed point of zero charge (PZC) of the amphoteric edges sites approximately similar to the purified samples, in the range ~7.5-8.5, ~8.2-8.7 and ~ 9.0-9.3 for
It(Mo), It(Ha) and It(Ga), respectively. The PZCs of freshly prepared dispersions are higher than those reported in the literature indicating basic character of these samples (pH of equilibrium suspensions in distilled water were ~7.9-9). In the present study, the focus was on the surface charge characteristics. A simple SCM model approach is presented to explain the illite H+ adsorption data. Surface weak acidic sites and surface ionization constants were calculated from titration data using regression methods. Sites with pKaint1 values of 6-6.7; 5.4-5.8; 6.1-6.6 and sites at pKaint2 values of 9.2-9.9; 10.2-10.4; 9.3-10 for It(Mo), It(Ga) and It(Ha), respectively, were assigned to amphoteric Al-OH and/or Fe-OH and Si-OH groups on the edges of illite samples.



12.
PHASE TRANSFORMATIONS OF CuCrS2: STRUCTURAL AND CHEMICAL STUDY

I. G. Vassilieva, T. Y. Kardash, V. V. Malakhov
Keywords: ternary copper-chromium-sulfide, partially ordered phases, structure, composition, phase transitions
Pages: 302-310

Abstract >>
The structure and composition of the CuCrS2 powder synthesized by sulfidation of a mixture of oxides Cu2O:Cr2O3 = 1:1 at 850°C and cooled to room temperature at a rate of 60°C/min were studied by X-ray powder diffraction and differentiating solution. A rhombohedral CuCrS2 phase (space group R3m) was found, which was stoichiometric in composition and had disordering in the copper sublattice because copper was arranged at the tetrahedral and octahedral sites with occupancy 10% at the latter. The structure of CuCrS2, in which the octahedra were occupied by copper atoms at room temperature, was found for the first time; in known structures, the copper atoms occupied only the tetrahedral sites, while the probability of octahedral occupation appeared around 400°Ñ (order−disorder transition). The partially disordered CuCrS2 phase is intermediate on the route to complete ordering. The quickly cooled CuCrS2 powder is unstable; after the second heating to 500°C with prolonged annealing at 390°C→180°C→80°C→25°Ñ, its transition to the stable state was accompanied by liberation of 2-4 wt.% Cu9S5. The real composition of ternary sulfide after isolation of the Cu9S5 phase is discussed using the data of the structural method, differential dissolution, and magnetic measurements.



13.
PHASE FORMATION IN THE SYSTEM (Z = 1.00). CRYSTAL STRUCTURE AND PROPERTIES OF SODIUM HETEROPOLYHEXATUNSTEN NICKELATE(2+)Na4[Ni(OH)6W6O18]·16H2O

G. M. Rozantsev, S. V. Radio, N. I. Gumerova, V. N. Baumer, Î. Â. Shishkin
Keywords: heteropoly compound, tungstate, sodium heteropolyhexatungsten nickelate (2+), Anderson-Evans structure, crystal structure, IR spectroscopy, X-ray diffraction analysis, thermal analysis
Pages: 311-319

Abstract >>
The green crystals of Ni1.5H[Ni(OH)6W6O18]·12.5H2O and blue crystals of Na4[Ni(OH)6W6O18]·16H2O were isolated from the acidified (to Z = ν(H+)/ν = 1.00) solutions of Ni(NO3)2-Na2WO4-HNO3-H2O systems. The synthesized salts were identified by chemical analysis, XRPA, and IR spectroscopy. It was shown that the heteropolyanions belonged to the Anderson-Evans type of structure. An X-ray diffraction study of Na4[Ni(OH)6W6O18]·16H2O was carried out (Mr = 1932.07, triclinic, space group P-1, a = 8.0089(11) Å, b = 10.5758(14) Å, c = 12.1987(16) Å; α = 69.268(13)°, β = 71.069(12)°, γ = 83.816(11)°; V = 914.0(2) Å3 at T = 293 K, Z = 1, ρcal = 3.510 g/cm3, F000 = 874, μ = 19.470 mm-1,
-16 ≤ h ≤ 16, -21 ≤ k ≤ 21, -24 ≤ l ≤ 24; the final R factors are RF = 0.0277, wR2 = 0.0469 for the observed reflections (RF = 0.0606, wR2 = 0.0523 for all independent reflections); S = 0.953; CSD-419883). The structure was solved by direct methods and refined in an anisotropic approximation. Hydrogen atoms were found in a difference synthesis and refined in an isotropic approximation with geometrical limitations. The nature of water in Na4[Ni(OH)6W6O18]·16H2O was characterized by DTA. XRPA was used to identify the thermolysis products of heteropoly compounds.



14.
STUDY OF THE Re0.50Rh0.50 PRODUCTS OF THERMOBARIC TREATMENT

S. A. Gromilov, T. V. D'yachkova, K. V. Yusenko, I. B. Kireenko, A. P. Tyutyunnik, Y. G. Zainulin
Keywords: rhodium, rhenium, solid substitution solution, high pressure, high temperature, X-ray phase analysis, thermolysis, microhardness
Pages: 320-324

Abstract >>
The products of thermobaric treatment of the metastable Re0.50Rh0.50 nanocrystalline phase (à = 2.733(2) Å, ñ = 4.364(4) Å, space group P63/mmc, CSR ~5 nm) in a high-pressure chamber were studied. Storage of the phase at 2000°Ñ and 1.5 GPa for 3 min led to the formation of a fused particle (∅~1 mm). The initial composition did not change, but the coherent scattering region (CSR) increased to 52 nm. An increase to 4 GPa in pressure also did not lead to a decomposition of the metastable Re0.50Rh0.50 phase, the unit cell parameters remained the same, and the size of the CSR increased by a factor of four.



15.
CRYSTAL-CHEMICAL ANALYSIS OF THE STRUCTURES OF MINERALS WITH [Hg2]2+ DUMBBELLS

S. V. Borisov, S. A. Magarill, N. V. Pervukhina
Keywords: atomic sublattices, crystal structures of [Hg2]2+-containing minerals, structure-forming factors
Pages: 325-334

Abstract >>
An analysis of the structures of minerals with [Hg2]2+ dumbbells including poyarkovite [Hg2]3Cl2O2, shakhovite [Hg2]2Sb(OH)3O3, vasilyevite Hg20O6I3Br2Cl(CO3), and kelyanite [Hg2]6[SbO6]BrCl2 was carried out. The determining factor in structure formation is the ordering of the centers of the cluster groups of mercury and large anions by systems of equidistant parallel planes with dhkl ~ 2.5-4.5 Å. The different combinations of atoms and fragments in the structure are ordered by their own pseudotranslation lattices; this probably reflects the stages of crystallization. The crystal structures under study are examples of balance between the local interatomic interactions and the forces that create long-range order for different stoichiometries, masses, and sizes of components.



16.
CRYSTAL STRUCTURE AND LUMINESCENCE OF ANTIMONY(III) BROMIDE WITH ANILINE

B. V. Bukvetskii, T. V. Sedakova, A. G. Mirochnik
Keywords: crystal structure, antimony(III), aniline, luminescence
Pages: 335-340

Abstract >>
The atomic structure of antimony(III) bromide crystals with anilinium was determined by X-ray diffraction analysis of (Ñ6H5NH3)2SbBr5 (a = 19.704(3) Å, b = 7.914(1) Å, c = 25.556(4) Å; space group Pbca, Z = 8, ρcalc = 2.365 g/cm3). The crystal structure consists of infinite chains of [SbBr5]2- complex anions formed by sharing six vertices and the anilinium (Ñ6H5NH3)+ cations, through which the chains are linked in layers by N-H…Br hydrogen bonds. The geometrical aspects that determine the luminescent spectral properties of the complex are discussed.



17.
TRANS-DINITRO- AND TRANS-DINITRATORUTHENIUM COMPLEXES [RuNO(NH3)2(NO2)2(OH)] AND [RuNO(NH3)2(H2O)(NO3)2]NO3·H2O

M. A. Il'in, E. V. Kabin, V. A. Emel'yanov, I. A. Baidina, V. A. Vorob'yov
Keywords: ruthenium, nitroso complexes, ammino complexes, nitro complexes, nitrato complexes, spent nuclear fuel, X-ray analysis
Pages: 341-348

Abstract >>
Methods for the synthesis of trans-diammino complexes [RuNO(NH3)2(NO2)2(OH)] (I) and [RuNO(NH3)2(H2O)(NO3)2](NO3)·H2O (II) are suggested. The compounds were studied by IR spectroscopy and X-ray phase and X-ray structural analyses. Crystal data: space group P-1; a = 6.2328(2) Å, b = 11.0488(3) Å, c = 11.0981(4) Å; α = 71.942(1)°, β = 83.291(1)°, γ = 86.877(1)° (I); space group P21; a = 6.6290(2) Å, b = 13.4389(5) Å, c = 7.0180(2) Å, β = 114.281(1)° (II). Complex II readily lost some part of crystal water on storage in open air.



18.
STRUCTURE AND THERMAL PROPERTIES OF [RhPy4CL2]X COMPLEX SALTS (X = CL-, ReO, ClO)

D. B. Vasilchenko, I. A. Baidina, E. Y. Filatov, S. V. Korenev
Keywords: rhodium, pyridine, perrhenate ion, perchlorate ion, X-ray analysis, thermal analysis
Pages: 349-356

Abstract >>
[RhPy4Cl2]Cl·4H2O (I), [RhPy4Cl2]ReO4 (II), [RhPy4Cl2]ClO4 (III), and [RhPy4Cl2]ReO4·2H2O complex salts were synthesized. The crystal structure of compounds II (P4/ncc, a = 25.5655(3) Å, c = 14.3521(4) Å), III (P21/n, a = 13.5308(3) Å, b = 15.1044(5) Å, c = 23.3457(8) Å, β = 93.327°), and dyhydrate of II (Pbcm, a = 10.6199(9) Å, b = 10.4964(9) Å, c = 22.9834(16)Å) was determined by X-ray diffraction analysis. The thermal transformations of the complexes were studied by differential thermal analysis. The substances were characterized by IR spectroscopy, XRPA, and element analysis



19.
DETERMINATION OF HYDROGEN ATOM POSITIONS IN BASIC LEAD CARBONATE HYDROCERUSSITE BY QUANTUM CHEMICAL METHODS AND SIMULATION OF THE VIBRATIONAL SPECTRA

M. R. Bissengaliyeva
Keywords: atomic positions, crystal structure, vibrational spectra, thermodynamic functions, quantum chemical calculation
Pages: 357-361

Abstract >>
Positions of hydrogen atoms in the crystal structure of basic lead carbonate hydrocerussite are determined by the ÐÌ5 quantum chemical method. Raman and infrared spectra as well as thermodynamic functions are calculated for this compound by the theory of crystal lattice dynamics.



20.
MOLECULAR STRUCTURE OF PARAMAGNETIC BIS-DIISOBUTYL DITHIOPHOSPHINATE COMPLEXES OF LANTHANIDES(III) WITH 1,10-PHENANTHROLINE IN SOLUTION BY THE DATA OF NMR RELAXATION SPECTROSCOPY

S. P. Babailov, V. L. Varand
Keywords: lanthanide-induced shifts, lanthanides, paramagnetic complexes of lanthanides, paramagnetic lanthanide-induced enhancement of spin-lattice relaxation rates, nuclear magnetic resonance (NMR), NMR relaxation spectroscopy, molecular structure, luminescent se
Pages: 362-364

Abstract >>
NMR relaxation spectroscopy (RS) is used to examine the molecular structure of paramagnetic bis-diisobutyl dithiophosphinate complexes of lanthanides (by the example of europium and lutetium) with 1,10-phenanthroline in CDCl3 solution. The results obtained are consistent with the results of studying the molecular structure of bis-diisobutyl dithiophosphinate complexes of yttrium with 1,10-phenanthroline in the crystalline phase by XRD.



21.
MÖSSBAUER SPECTRA OF IRON DOPED CuCrS2

V. A. Varnek, V. V. Sokolov, I. Y. Filatova, S. A. And
Keywords: sulfides, iron, M?ssbauer spectra, phase composition, structure
Pages: 365-368

Abstract >>
Mössbauer spectroscopy is used to study the state of iron atoms in samples with a composition of
CuCr1-xFexS2 (x = 0.01-0.30). It is shown that at x ≤ 0.02 samples are solid solutions in which iron atoms have an oxidation number of 3+ and replace chromium atoms in octahedral sites. When the iron concentration increases, the second phase - chalcopyrite CuFeS2 - forms along with the solid solution. The relative iron concentration in this phase increases from 11% at x = 0.03 to 52% at x = 0.30.



22.
INTERRUPTED SUPER FRAMEWORK OF THE CRYSTAL STRUCTURE OF Cs[Be2(PO4)(PO4H)] CESIUM DIBERYLLIUM PHOSPHATE HYDROPHOSPHATE

V. V. Bakakin, Y. V. Seretkin, S. P. Demin
Keywords: crystal structure, cesium beryllium phosphate, para framework, super framework
Pages: 369-373

Abstract >>
The crystal structure of cesium diberyllium phosphate hydrophosphate Cs[Be2(PO4)(PO4H)] obtained hydrothermally is analyzed. Unit cell parameters are: a = 4.8860(5) Å, b = 10.7330(11) Å, c =
13.0061(15) Å, α = 92.540(10)°, β = 92.451(9)°, γ = 90.948(9)°, space group P 1. In the structural motif consisting of ÐÎ4 and ÂåÎ4 tetrahedra, Âå,Ð two-link chains and ribbons are distinguished, typical of a short a-translation of ≈4.9 Å. The presence of ternary and terminal O ligands along with bridging ones determines the term interrupted super framework. The group of two Âå tetrahedra with a common edge is detected for beryllium phosphates for the first time.



23.
CRYSTAL STRUCTURE OF A NEW POLYMORPHIC MODIFICATION OF β-K2[Pd(NO3)4]

S. P. Khranenko, I. A. Baidina, S. A. Gromilov
Keywords: palladium, nitrates, coordination compounds, crystal structure, crystal chemistry
Pages: 374-377

Abstract >>
X-ray diffraction is applied to study a new crystalline modification of K2[Pd(NO3)4]-β-K2[Pd(NO3)4]. It is found that the phase is isostructural with Na2[Pd(NO3)4] and Rb2[Pd(NO3)4]. Square coordination of the Pd atom is formed by oxygen atoms of monodentately coordinated nitrate groups.



24.
CRYSTAL STRUCTURE OF THE BIOCTAHEDRAL CLUSTER COMPLEX K6[Re12Cs17(CN)6]·2CH3OH·10H2O

Y. V. Mironov, S.-J. Kim, V. E. Fedorov
Keywords: rhenium, bioctahedral thiocyanate cluster, synthesis, crystal structure
Pages: 378-380

Abstract >>
The cluster complex of K6[Re12CS17(CN)6]·2CH3OH·10H2O composition is separated by recrystallization of the K6[Re12CS17(CN)6]·20H2O compound from methanol. The compound crystallizes in hexagonal space group P-6m2 with unit cell parameters: a = 10.9932(14) Å, c = 14.631(4) Å, V = 1531.3(5) Å3, Z = 1, and dcalc = 3.720 g/cm3.



25.
CRYSTAL STRUCTURE OF [Mn(1,10-C12H8N2)3](B6H7)2

T. M. Polyanskaya, M. K. Drozdova, V. V. Volkov, K. G. Myakishev
Keywords: [tris-phenanthroline manganese(II)](2+) cation, heptahydro-closo-hexaborate(1-) anion, single crystal X-ray diffraction analysis
Pages: 381-385

Abstract >>
A new compound is synthesized; its crystal structure is studied by XRD at 100 K. Crystallographic data: C36H38B12N6Mn, M = 739.39, triclinic symmetry, space group unit cell parameters: a = 10.3131(3) Å, b = 13.4839(4) Å, c = 15.1132(4) Å; α = 97.696(1)°, β = 108.324(1)°, γ =
102.211(1)°; V = 1903.9(1) Å3, Z = 2, dcalc = 1.290 g/cm3. The structure is solved by direct and Fourier methods and refined by full-matrix LSM in the anisotropic (isotropic for hydrogen atoms) approximation to the final factor R1 = 0.036 for 10169 Ihkl ≥ 2σI (Bruker-Nonius X8 APEX CCD diffractometer, λMoKα). The structure contains two crystallographically different anions.



26.
CRYSTAL STRUCTURE OF A TWO-DIMENSIONAL CO(II) COORDINATION POLYMER: [Co(μ-PP)2(SCN)2]n [PP = 2-(PYRIDINE-3-YLOXY)PYRAZINE]

H. Li, H.-Y. Zhao, S.-G. Zhang, J.-M. Shi
Keywords: crystal structure, cobalt(II) complex, 2D polymer, layered structure
Pages: 386-390

Abstract >>
Solvothermal reaction (water/methanol) of cobalt perchlorate hexahydrate, sodium thiocyanate and 2-(pyridine-3-yloxy)pyrazine (PP) resulted in the formation of a two-dimensional coordination polymer [Co(μ-PP)2(SCN)2]n. The solid complex has been characterized by elemental analysis and IR spectroscopy; its crystal structure was determined by X-ray crystallography. The complex crystallizes in the monoclinic system, space group P21/n, a = 7.4643(19), b = 9.237(2), c = 15.540(4) Å, β = 94.995(5)°, V = 1067.4(5) Å3, Z = 1. In the crystal structure each 2-(pyridine-3-yloxy)pyrazine molecule acts as a bidentate bridging ligand coordinating to two adjacent Co(II) ions with Co…Co separation of 9.5176(18) Å to yield a two-dimensional sheet structure in the plane (-1 0 1).



27.
MOLECULAR AND CRYSTAL STRUCTURE OF A NEW COMPOUND METHYL-18R-13-ISOPROPYL-10A,7-DIMETHYL-4-OXO-1-OXAHEXACYCLO×[12.4.0.05À,4A.013,1201,1A.010A,6À]HENEICOSANE-7-CARBOXYLATE

I. E. Smirnova, E. V. Tret'yakova, O. B. Kazakova, Z. A. Starikova, I. V. Fedyanin
Keywords: methyl-18R-13-isopropyl-10à,7-dimethyl-4-oxo-1-oxahexacyclo[12.4.0.05à,4a.013,12.01,1a.010a,6à]? heneicosane-7-carboxylate, synthesis, X-ray diffraction analysis
Pages: 391-392

Abstract >>
Synthesis is performed and the molecular structure is analyzed of methyl-18R-13-isopropyl-10à,7-dimethyl-4-oxo-1-oxahexacyclo[12.4.0.05à,4a.013,12.01,1a.010a,6à]heneicosane-7-carboxylate II. Compound II Ñ27H40O4 crystallizes in orthorhombic symmetry with cell parameters: à = 11.9915(15) Å, b = 12.1674(16) Å, c = 15.8094(17) Å, space group P212121, Z = 4, d = 1.234 g/cm3.



28.
MOLECULAR AND CRYSTAL STRUCTURE OF METHYL-4-ANTI-HYDROXYIMINO-1-DIOXOLANO-13-ISOPROPYL-10À,7-DIMETHYLPENTACYCLO×[10B.8.5.04B,10B.06À,10À.01À,4A]ICOS-14-ENE-7-CARBOXYLATE

I. E. Smirnova, E. V. Tret'yakova, O. B. Kazakova, Z. A. Starikova
Keywords: methyl-4-anti-hydroxyimino-1-dioxolano-13-isopropyl-10à,7-dimethylpentacyclo? [10b.8.5.04b,10b.06à,10à.01à,4a]icos-14-ene-7-carboxylate, synthesis, single crystal X-ray diffraction analysis
Pages: 393-395

Abstract >>
Synthesis is performed and the molecular structure is analyzed of methyl-4-anti-hydroxyimino-1-dioxolano-13-isopropyl-10à,7-dimethylpentacyclo[10b.8.5.04b,10b.06à,10à.01à,4a]icos-14-ene-7-carboxylate IIa. Compound IIa Ñ27H40O4 crystallizes in monoclinic symmetry with cell parameters: à = 13.785(13) Å, b = 7.302(7) Å, c = 13.817(13) Å, β = 94.799(19)°, space group Ð2(1), Z = 2, d = 1.164 g/cm3.



29.
NEW POLYMORPHIC MODIFICATION OF THE CRYSTAL STRUCTURE OF BROMOPEGANOL

R. Y. Okmanov, A. G. Tozhiboev, K. K. Turgunov, B. Tashkhodzhaev, N. I. Mukarramov, K. M. Shakhidoyatov
Keywords: alkaloids, quinazolines, polymorphism, X-ray diffraction analysis
Pages: 396-398

Abstract >>
The crystal structure of 6-bromopeganol in a new polymorphic modification is found and determined by single crystal X-ray diffraction analysis. For the crystal structure of the new polymorph the formation of a centrosymmetric closed dimer (associate) is also characteristic. It consists of two bromopeganol molecules bound by centrosymmetric reciprocal hydrogen bonds O-H…N(1). This polymorph differs from the known one in the mutual arrangement and interaction of these associates.



30.
MOLECULAR AND CRYSTAL STRUCTURE OF 23,24,25,26,27,29,30-HEPTAMETHYL-19,28- OXAHEXACYCLO[15.13.18.017,18.013,14.08,9.05,10]TETRACOS-3-YL ACETATE

N. I. Medvedeva, O. B. Flechter, A. A. Korlyukov
Keywords: 23,24,25,26,27,29,30-heptamethyl-19,28-oxahexacyclo[15.13.18.017,18.013,14.08,9.05,10]tetracos-3-yl acetate, X-ray analysis.
Pages: 399-401

Abstract >>
The molecular structure of 23,24,25,26,27,29,30-heptamethyl-19,28-oxahexacyclo[15.13.18.017,18.013,14.08,9.05,10]tetracos-3-yl acetate III. Compound III Ñ32H52O3 crystallizes in the monoclinic crystal system with the unit cell parameters à = 13.265(15) Å, b = 6.481(7) Å, c = 32.274(4) Å, β = 99.333(2)°, space group Ñ2, Z = 4, d = 1.176 g/cm3.