In the work the double differentiation of functions describing the Pt4 f 7/2 band in the XPS spectra of model supported Pt/SiO2 catalysts is performed in order to determine the number of different chemical states of platinum particles. The functions for the differentiation are obtained by the deconvolution of the experimental spectral contour into two spin-orbit components. As a result of the performed analysis of the number and position of the minima of the second derivative of the function of Pt4 f 7/2 the conditions of the oxidation of platinum particles in the Pt/SiO2 sample on treating in a NO + O2 mixture and the reduction of platinum oxide particles on interacting of the PtO x /SiO2 sample with hydrogen are determined.
P.Yu. Tyapkin1,2, S.A. Petrov1, A.P. Chernyshev1,3, A.I. Ancharov1,2,4, L.A. Sheludyakova5, N.F. Uvarov1,2,3 1Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 2Novosibirsk National Research State University, Novosibirsk, 630090 Russia 3Novosibirsk State Technical University, Novosibirsk, 630073 Russia 4Budker Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 5Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia
Keywords: оксалат железа, мессбауэровская спектроскопия, рентгеновская дифракция, синхротронное излучение, ИК спектроскопия, метастабильная аморфная фаза, iron oxalate, Mössbauer spectroscopy, X-ray diffraction, synchrotron radiation, IR spectroscopy, metastable amorphous phase
The existence of hydrate forms of iron(III) oxalate, which noticeably differ from each other in the Mössbauer spectral parameters (isomer shift and quadrupole splitting), is detected. In the assumption of the formation of phases with different structural characteristics the samples of the compound under study are studied by the powder X-ray diffraction analysis (including the application of synchrotron radiation), Mössbauer and IR spectroscopy. It is shown that the phase characterized by new values of the Mössbauer parameters has its own IR spectrum and it is X-ray amorphous and metastable.
By the classical molecular dynamics method liquid chlorobenzene chlorobenzene is modeled in the temperature range 293-363 K. The radial angular distribution functions are calculated for the distances between the benzene ring planes and the angle between them; the radial distribution functions for the distances between the chlorine atoms; self-diffusion coefficients, local dipole moments, and the permittivity. In the whole temperature range the molecules are combined into agglomerates due to contacts between the chlorine atoms (halogen aggregation) and owing to specific interactions of benzene rings which result in their mainly parallel and perpendicular orientations in the first coordination sphere. Molecules in the agglomerates are mostly organized in the 1D motif: chains of chlorine atoms and stacks of benzene rings. With an increase in the temperature the structure of agglomerates is reorganized and changes are most obvious in temperature ranges 293-298 K, 313-323 K, and 343-353 K.
L.N. Zelenina1,2, T.P. Chusova1, N.V. Podberezskaya1, I.V. Korol`kov1,2, D.A. Piryazev1,2 1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 2Novosibirsk National Research State University, Novosibirsk, 630090 Russia
Keywords: полиселениды гадолиния, термодинамическое моделирование, выращивание кристаллов газотранспортными методами, рентгенофазовый и рентгеноструктурный анализ, gadolinium polyselenides, thermodynamic simulation, crystal growth by nitrogen-transport methods, powder and single crystal X-ray diffraction analysis
Optimal growth conditions for GdSe1.85 crystals are found by the thermodynamic simulation of the Gd-Se-I system. The obtained data are used to grow GdSe1.85 crystals by the transport method using iodine as a transport agent. The grown crystals are identified by microprobe and powder X-ray diffraction analyses. The structure is determined by the single crystal X-ray diffraction analysis and the composition is refined. The crystal structure is in general typical of the structures of REM polychalcogenides, however, the unit cell represents the metric type unknown previously: a = 4.0562(2), b = 8.1065(5), c = 9.2489(5) , a = 115.9990(10), b = 90.000(2), g = 89.9750(10), V = 273.34(3) 3, Z = 4, d calc = 7.659 g/cm3, space group Pb 11. The experimental material for the X-ray crystallographic analysis is obtained on an automated Bruker X8 APEX diffractometer (Мо K radiation, graphite monochromator, CCD detector resolution 10241024 pixel, distance to the detector L = 50 mm, rotation about the axis 15 min) by the standard procedure, 2274 measured reflections, out of them 1523 independent ( R (int) = 0.0352), R -factor [ I > 2s( I )] = 0.0517, R -factor (all measured) = 0.0694).
Novel supramolecular networks based on an anionic polymolybdophosphate cluster Sr10(H2O)12[Sr2P9HMo12O71] is hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, thermogravimetric analysis, infrared, ultraviolet spectroscopy, and cyclic voltammetry in an aqueous solution. It crystallizes in the orthorhombic space group Pnmm (No. 59) with a = 12.699(1), b = 14.914(1), c = 23.851(2) Å and Z = 2. The compound is made up of unusual shaped-cage [Sr2P9HMo12O71]20-. The strontium cations are divided in two kinds. The first occupy vacant sites in the [P9Mo12O68] n- polyoxoanions unit and the second [Sr(H2O)6]2+, [Sr(H2O)4]2+, and [Sr(H2O)2]2+ serve to bridge together the adjacent polymolybdophosphate clusters to yield unprecedented three-dimensional pure inorganic assemblies of the shaped-cage polymolybdophosphate clusters.
By single crystal X-ray diffraction and differential thermal analyses tetramethylammonium hexafluoridozirconate (N(CH3)4)2[ZrF6] is studied. In the temperature range 96-110 C the crystals undergo a reversible phase transition from the low-temperature trigonal modification (space group R ) to the high-temperature cubic one (space group Fmm ). The cubic phase is composed of regular [ZrF6]2- octahedra and tetrahedral (CH3)4N+ cations bound by ionic interactions and С-H⋯F hydrogen bonds.
M.J. Plater, B.M. De Silva, M.R. St J. Foreman, W.T.A. Harrison
University of Aberdeen, Aberdeen, Scotland
Keywords: manganese, coordination polymer, flexible ligand
The syntheses and crystal structures of two one-dimensional coordination polymers, [Mn(C5HO2F6)2(C16H20N2)] n (1) and [Mn(C5HO2F6)2(C20H20N2)] n (2), are described, where is the hexafluoro acetylacetonate anion, C16H20N2 is 1,6-bis(4-pyridyl)-hexane, and C20H20N2 is 1,4-bis[2-(3-pyridyl)ethyl]-benzene. In both phases, the metal ion lies on a crystallographic twofold axis and is coordinated by two chelating anions and two bridging bipyridyl ligands to generate a cis -MnN2O4 octahedron. The bridging ligands, which are completed by crystallographic inversion symmetry in both compounds, connect the metal nodes into zigzag [20 ] chains in 1 and contorted [001] chains in 2. Intrachain C-H⋯O interactions occur in 1 but not in 2, which may be correlated with the relative orientations of the ligands. Crystal data: 1, C26H22F12MnN2O4, M r = 709.40, monoclinic, C 2/ c (No. 15), a = 9.3475(2) Å, b = 16.6547(3) Å, c = 18.3649(4) Å, b = 91.1135(8)°, V = 2858.50(10) Å3, Z = 4, R ( F ) = 0.030, wR ( F 2) = 0.075. 2, C30H22F12MnN2O4, M r = 757.44, monoclinic, C 2/ c (No. 15), a = 19.9198(2) Å, b = 10.6459(2) Å, c = 16.8185(3) Å, b = 119.8344(8)°, V = 3093.91(9) Å3, Z = 4, R ( F ) = 0.032, wR ( F 2) = 0.078.
A new mixed-ligand one-dimensional copper(II) coordination polymer [Cu(en)(sal)Cl] n where en = ethylenediamine(C2H8N2) and Hsal = 2-hydroxybenzoic acid (salicylic acid; C7H6O3) is synthesized and characterized by FTIR spectroscopy and single crystal X-ray diffraction. The structure contains Cu2+ ions in two different distorted octahedral coordination environments: an axially extended CuN4Cl2 moiety arising from a pair of bidentate en ligands and a CuO4Cl2 moiety arising from a pair of asymmetrically coordinated sal- anions. The chloride ions bridge the copper ions into a zigzag chain propagating in [001]. The structure is consolidated by N-H⋯O and N-H⋯Cl hydrogen bonds which generate a layered network. Crystal data: C9H13ClCuN2O3, M r = 296.20, monoclinic, P 21/ c , a = 13.9179(10) Å, b = 10.4900(8) Å, c = 8.5181(6) Å, b = 105.518(4)°, V = 1198.30(15) Å3, Z = 4, R ( F ) = 0.026, wR ( F 2) = 0.068.
A.N. Makhinya1,2, M.A. Il`in1,2, I.A. Bai`dina1, I.V. Korol`kov1,2 1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 2Novosibirsk National Research State University, Novosibirsk, 630090 Russia
Keywords: рутений, нитрозокомплексы, амминокомплексы, сульфатокомплексы, хлорокомплексы, синтез, рентгеноструктурный анализ, ИК спектроскопия, ruthenium, nitroso complexes, ammino complexes, sulfato complexes, chloro complexes, synthesis, X-ray crystallography, IR spectroscopy
After the addition of the saturated NaClO4 solution to the solution of trans -[Ru(NO)(NH3)4SO4] HSO4H2O, trans -[Ru(NO)(NH3)4SO4]ClO4 perchlorate salt (I) is obtained with an yield of 80 %. The heating of trans -[Ru(NO)(NH3)4(H2O)](HSO4)SO4 at a temperature of 220 C results in a complete removal of coordination water and a partial removal of ammonia molecules. At successive treatment of the thermolysis product with sulfuric and hydrochloric acids [Ru(NO)(NH3)4SO4][Ru(NO)(NH3)3Cl(SO4)]HSO4H2O crystals (II) are obtained. By X-ray crystallography the structure of the obtained compounds is determined: for I space group P 21/ c , a = 6.6949(9), b = 13.7049(19), c = 12.8641(17) , = 101.028(4); for II, space group Р 21/ c , a = 14.1304(4), b = 12.4908(3), c = 11.6264(3) , = 94.1980(10).
In the work isomeric complexes of platinum(II) with the (ptac)-1- Pt((CH3)3-CO-CH-CO-CF3)2 pivaloyltrifluoroacetonate ion are studied. The synthesis and chromatographic separation of Pt(ptac)2 isomers is described, TGA data for the separated isomers are given, and the crystal structures of solid phases are studied. The cis -Pt(ptac)2 complex crystallizes in the space group Р -1, a = 10.7091(4), b = 12.7787(6), c = 16.0154(8) , = 92.389(2), = 90.868(2), = 112.1260(10), V = 2027.39(16) 3, Z = 4, d calc = 1.918 g/cm3. The trans -Pt(ptac)2 complex crystallizes in the space group C 2/ m , a = 13.3235(5), b = 8.5515(3), c = 9.6694(3) , = 118.5880(10), V = 967.38(6) 3, Z = 2, d calc = 2.010 g/cm3. The structures of the complexes are molecular, the Pt atom has a square coordination of four oxygen atoms of two ligands; for cis- Pt(ptac)2 the Pt-Oav distance is 1.968 , for trans -Pt(ptac)2 it is 1.980 .
