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1.
V. D. Živanović S. R. Grujić M. B. Tošić N. S. Blagojević J. D. Nikolić 《Journal of Thermal Analysis and Calorimetry》2009,96(2):427-432
The crystallization of K2O·TiO2·3GeO2 glass under non-isothermal condition was studied. In powdered glass with particle sizes less than 0.15 mm, surface crystallization
was dominant and an activation energy of crystal growth of E
a,s=327±50 kJ mol−1 was calculated. In the size range 0.15 to 0.45 mm, both surface and volume crystallization occurred. For particle sizes >0.45
mm, volume crystallization dominated with spherulitic morphology of the crystals growth and E
a,v=359±64 kJ mol−1 was calculated. 相似文献
2.
3.
Single crystal X-ray diffraction study of glycine phosphite C2H5NO2·H3PO3 was performed (monoclinic, space group P21/c, a = 7.401(3) Å, b = 8.465(3) Å, c = 9.737(3) Å; β = 100.73(5)°, Z = 4). It has been found that one of hydrogen atoms is located at the centre of symmetry forming two strong hydrogen bonds to yield H4P2O 6 ?2 dimers, while another hydrogen atom is statistically disordered over two positions and organizes the dimers into an infinite corrugated chain. The ordering of this hydrogen atom position and/or displacement of the other one from the centre of symmetry will lead to the loss of symmetry centre and lowering of the point group symmetry from C2h to piezo-active group C2 or C s . 相似文献
4.
The dependence of solid phase composition on the main parameters of the interaction in the CoSO4-K4P2O7-H2O system was studied. The synthesis conditions were determined and a crystalline cobalt(II) diphosphat of the composition
Co2P2O7 · 6H2O was synthesized. Its thermal properties were studied. The composition and the intervals, wherein the thermally stable products
of partial and complete dehydration of Co2P2O7 · 6H2O are formed, were specified. The final heat treatment product, anhydrous α-Co2P2O7, was identified and a sequence of the solid phase thermal transformations accompanying its formation was established. 相似文献
5.
Norio Saito Pierric Lemoine Noée Dumait Maria Amela-Cortes Serge Paofai Thierry Roisnel Vivian Nassif Fabien Grasset Yoshiki Wada Naoki Ohashi Stéphane Cordier 《Journal of Cluster Science》2017,28(2):773-798
We report here the synthesis, the crystal structure and the luminescent properties of the new cluster compounds Cs2Mo6Cl14·H2O and Cs2Mo6Br14·H2O. Single-crystal X-ray diffraction performed on Cs2Mo6Cl14·H2O indicates that the compound crystallizes in the monoclinic space group C2/c with refined cell parameters a = 19.578 Å, b = 15.151 Å, c = 9.347 Å, and β = 115.64°. The structure can be described from discrete \(\left[ {{\text{Mo}}_{ 6} {\text{Cl}}^{\text{i}}_{ 8} {\text{Cl}}^{\text{a}}_{ 6} } \right]^{ 2- }\) anionic cluster units arranged in a “A–A’–A–A’” pseudo prismatic stacking parallel to (b, c) plane with both Cs+ cations and water molecules located between the layers. Moreover, the centric character of the trigonal structure of Cs2Mo6Cl14 was also studied by combination of single-crystal X-ray diffraction and both X-ray and neutron powder diffraction. The results suggest an important influence of the sample preparation on the symmetry of the crystal structure. The crystal structure relationship between the \(\left[ {{\text{Mo}}_{ 6} {\text{Cl}}^{\text{i}}_{ 8} {\text{Cl}}^{\text{a}}_{ 6} } \right]^{ 2- }\) anionic cluster unit arrangements in Cs2Mo6Cl14 and Cs2Mo6Cl14·H2O is discussed. Finally, the characterization of the luminescent properties of Cs2Mo6X14 and Cs2Mo6X14·H2O (X = Cl, Br) indicates that emission profile is comparable regardless existence of water molecule in the crystal structure. 相似文献
6.
D. V. Korchagin E. I. Zhilyaeva G. V. Shilov N. S. Ovanesyan S. M. Aldoshin 《Russian Journal of Inorganic Chemistry》2009,54(2):226-231
Single crystals of the Na4[Na2Cr2(C2O4)6] · 10H2O complex were synthesized for the first time. The structure of the complex was determined by X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system with the unit cell parameters a = 17.290(4) Å, b = 12.521(3) Å, c = 15.149(3) Å, β = 100.45(3)°, Z = 4, space group Cc. Anionic layers [NaCr(C2O4)3] 2n 4n? can be distinguished in the crystal structure of the complex. The Na+ cations and water molecules, involved in the formation of a hydrogen bond network, are located between the anionic layers. 相似文献
7.
Zh. V. Akhmerkina E. V. Peresypkina A. V. Virovets L. B. Serezhkina 《Russian Journal of Inorganic Chemistry》2008,53(9):1396-1400
Single crystals of Ba3[UO2(C2O4)2(NCS)]2 · 9H2O are synthesized and studied by X-ray diffraction. The crystals are orthorhombic, space group Fddd, Z = 16, and the unit cell parameters are a = 16.253(3) Å, b = 22.245(3) Å, c = 39.031(6) Å. The main crystal structural units are mononuclear complex groups [UO2(C2O4)2NCS]3? of the crystal-chemical family (AB 2 01 M1 (A = UO 2 2+ , B01 = C2O 4 2? , M1 = NCS?) of the uranyl complexes linked into a three-dimensional framework by electrostatic interactions and hydrogen bonds involving oxalate ions and water molecules. 相似文献
8.
V. N. Serezhkin A. G. Verevkin O. P. Smirnov V. P. Plakhtii 《Russian Journal of Inorganic Chemistry》2010,55(10):1600-1606
A powder of deuterated rubidium diselenatouranylate dihydrate Rb2UO2(SeO4)2 · 2D2O has been studied by neutron diffraction. The compound is orthorhombic, space group Pna21, with the following unit cell parameters: a = 13.654(2) Å, b = 11.863(2) Å, c = 7.625(1) Å, Z = 4, R F = 3.77, R I = 6.12, and χ2 = 2.21. Basic structure units are [UO2(SeO4)2 · D2O]2? layers belonging to the AB 2 2 M1 crystal-chemical group (A = UO 2 2+ , B2 = SeO 4 2? , M1 = D2O) of uranyl complexes. The hydrogen atoms if the water molecules involved in the layer form intralayer hydrogen bonds with the terminal oxygen atoms of selenate ions. The outer-sphere water molecules are coordinated to the rubidium ions and are involved in hydrogen bonding with oxygen atoms of neighboring [UO2(SeO4)2 · D2O]2? layers. 相似文献
9.
Nanorods of orthorhombic V3O7 · H2O with the parameters a = 16.805 Å, b = 9.428 Å, and c = 3.660 Å are prepared under hydrothermal conditions (T = 180–190°C, τ = 30–40 h) from the V2O5 · nH2O/H2C2O4 · 2H2O composite. The particle diameter is 40–70 nm, and the length is several micrometers. The IR spectra, electric conductivity, and thermal properties of the nanorod powder are studied. In air V3O7 · H2O begins to decompose at temperatures above 150°C, and at 350°C nanobelts V2O5 40–100 nm wide and 40 µm long are formed. A mechanism of nanostructure formation is suggested. 相似文献
10.
G. V. Lavrova N. V. Bulina V. S. Min’kov A. A. Matvienko 《Russian Journal of Inorganic Chemistry》2016,61(3):284-290
The thermal transformations of disubstituted cesium orthophosphate crystal hydrate under heating in air up to 400°C have been studied. The dehydration process occurs in two stages with the loss of 0.6 water molecules at 60?100°C and 1.4 water molecules at 100?160°C. Anhydrous Cs2HPO4 is stable up to 300°C and is completely converted into cesium pyrophosphate Cs4P2O7 at 330°C. The structure of Cs2HPO4 · 2H2O has been determined. The compound crystallizes in monoclinic space group P21/c and has the unit cell parameters a = 7.4761(5) Å, b = 14.2125(8) Å, c = 7.9603(6) Å, β = 116.914(5)°, V = 754.20(9) Å3, and Z = 4 at?123°C. An earlier unknown polymorph of Cs4P2O7 has been found. According to X-ray powder diffraction data, hexagonal space group Р63 has been proposed for the formed pyrophosphate. 相似文献
11.
A new composite, Li2MnO3·LiNi0.5Co0.45Fe0.05O2, can be synthesized by a solid-state method and preconditioned with 5 wt% HCl, H2SO4, or H3PO4 solution to achieve H+/Li+ exchange. The effects of acid treatment on the structure, morphology, and electrochemical properties of Li2MnO3·LiNi0.5Co0.45Fe0.05O2 cathode materials are analyzed. The X-ray powder diffraction patterns imply that the hexagonal α-NaFeO2 structure (space group R\(\bar{3}\)m) of the materials is not changed by the acid treatment. The scanning electron microscope images show that particles become spherical with smooth surfaces after acid treatment, and the Brunauer–Emmett–Teller analysis reveals that the specific surface area increases. The charge–discharge test demonstrates that acid-treated Li2MnO3·LiNi0.5Co0.45Fe0.05O2 cathode materials deliver higher initial coulombic efficiencies than untreated material, owing to the improvement of the catalytic reduction activity of oxygen released during the initial charge process. Furthermore, Li2MnO3·LiNi0.5Co0.45Fe0.05O2 treated with HCl displays the best electrochemical performance, with the acid treatment improving the initial coulombic efficiency from 66.0 to 82.2%. Thus, acid treatment can effectively improve the electrochemical performance of electrode materials in Li-ion batteries. 相似文献
12.
L. B. Serezhkina E. V. Peresypkina S. A. Novikov A. V. Virovets V. N. Serezhkin 《Russian Journal of Inorganic Chemistry》2012,57(1):41-45
Synthesis and X-ray diffraction study of [UO2CrO4(C5NH5COO)] · H2O crystals were performed. The compound crystallizes in the monoclinic system with the unit cell parameters a = 7.5025(3) Å, b = 11.5188(6) Å, c = 13.0518(6) Å, β = 97.877(4)°, V = 1117.29(9) Å3, space group P21/n, Z = 4, R = 0.0263. The structure is formed by three [UO2CrO4(C5NH5COO)] layers parallel to (10\(\bar 1\)). The coordination polyhedron of uranium atoms is a pentagonal bipyramid, whose apices are occupied by oxygen atoms of uranyl, three chromate groups, and two molecules of isonicotinic acid. Crystal chemical formula of the [UO2CrO4(C5NH5COO)] layer can be represented as AT3B2, where A = UO 2 2+ , T3 = CrO 4 2? , and B2 = C5NH5COO molecules. The isonicotinic acid molecules are in the form of zwitterions. 相似文献
13.
I. A. Baidina V. D. Il’yashevich V. F. Malakhov A. V. Belyaev 《Journal of Structural Chemistry》2007,48(5):973-976
The complex Na3(NH4)2[Ir(SO3)2Cl4]·4H2O was examined with single crystal X-ray diffraction and IR spectroscopy. Crystal data: a = 7.3144(4) Å, b = 10.0698(5) Å, c = 12.3748(6) Å, β = 106.203(1)°, V = 875.26(8) Å3, space group P21/c, Z = 2, d calc = 2.547 g/cm3. In the complex anion two trans SO 3 2? groups are coordinated to iridium through the S atom. The splitting of O-H bending vibrations of crystallization water molecules and N-H ones of the ammonium cation is considered in the context of different types of interactions with the closest neighbors in the structure. 相似文献
14.
A new compound containing the tetraphenylphosphonium cation and the nickel(III) bisdicarbollyl anion, [(C6H5)4P][Ni(B9C2H11)2]·CCl4, was synthesized and investigated by XRD at room temperature (295 K). Crystal data: C29H42B18PCl4Ni, M = 816.69, monoclinic, space group P2/c; unit cell parameters a = 13.5873(6) Å, b = 7.1475(2) Å, c = 20.7829(8) Å, β = 94.4595(13)°, V = 2012.2(2) Å3, Z = 2, d calc = 1.348 g/cm3. The structure was solved by direct and Fourier methods and refined by the full-matrix least squares method in an anisotropic (isotropic for H) approximation to the final R 1 = 0.0466 for 3055 I hkl ≥ 2σ I of 23,655 reflections collected and 5618 independent I hkl (Bruker X8 APEX diffractometer, λMoK α). 相似文献
15.
L. B. Serezhkina E. V. Peresypkina A. V. Virovets I. V. Medrish D. V. Pushkin 《Russian Journal of Inorganic Chemistry》2009,54(10):1577-1580
Single crystals of Cs[(UO2)2(C2O4)2(OH)] · H2O were synthesized and structurally studied using X-ray diffraction. The compound crystallizes in monoclinic space group P21/m, Z = 2, with the unit cell parameters a = 5.5032(4) Å, b = 13.5577(8) Å, c = 9.5859(8) Å, β = 97.012(3)°, V = 709.86(9) Å3, R = 0.0444. The main building units of crystals are [(UO2)2(C2O4)2(OH)]? layers of the A2K 2 02 M2 (A = UO 2 2+ , K02 = C2O 4 2? , and M2 = OH?) crystal-chemical family. Uranium-containing layers are linked into a three-dimensional framework via electrostatic interactions with outer-sphere cations and hydrogen bonds with water molecules. 相似文献
16.
The (VO)0.09V0.18Mo0.82O3 · 0.54H2O microrods of hexagonal symmetry system with the unit cell parameters a = 10.586 Å and c = 3.698 Å were obtained for the first time under hydrothermal conditions (T = 160°C, τ = 30?50 h). Particles were 1–2 μm in diameter and up to 45 μm in length. The compound is thermally stable up to 469°C. The core-electron Mo3d, V2p, and O1s and valence-band X-ray photoelectron spectra and IR spectra of the samples were studied. The molybdenum atoms in the complex oxide have the oxidation state Mo6+. The vanadium atoms introduced into the h-MoO3 lattice in molybdenum positions have the oxidation state V5+. Approximately one-third of vanadium atoms as vanadyl ions (VO)2+ are located in the channels of h-MoO3 lattice, thus stabilizing the latter. 相似文献
17.
V. G. Ponomareva I. N. Bagryantseva G. V. Lavrova 《Russian Journal of Electrochemistry》2017,53(6):636-640
The Cs2HPO4 · 2H2O single crystals synthesized from an aqueous solution containing equimolar amounts of H3PO4 and Cs2CO3 were studied by impedance and IR spectroscopy, X-ray diffraction analysis, and differential scanning calorimetry (DSC). The IR spectra were analyzed in accordance with the structural data, and the absorption bands were assigned. The proton conductivity was studied at temperatures in the range 20–250°C. The conductivity of dehydrated Cs2HPO4 was low, ~10–5–10–9 S cm–1 at 90–250°C with an activation energy of conductivity E a = 1.1 eV at 130–250°C. The processes determining the character of the temperature dependence of conductivity were consistent with the DSC and thermogravimetry data. According to these data, dehydration of the crystalline hydrate Cs2HPO4 · 2H2O starts at 60°C and occurs in three stages, forming Cs2HPO4 · 1.5H2O below 100°C; anhydrous Cs2HPO4 at t > 160°C, which is stable up to 300°C; and Cs4P2O7 above 330°C. 相似文献
18.
P. S. Gordienko A. P. Suponina S. B. Yarusova S. B. Bulanova G. F. Krysenko V. A. Kolzunov 《Russian Journal of Applied Chemistry》2009,82(9):1505-1509
The possibility and kinetic aspects of formation of X-ray amorphous calcium monosilicate in the model system CaSO4·2H2O-Na2O·SiO2 at room temperature were studied. 相似文献
19.
I. A. Kyuntsel 《Journal of Structural Chemistry》2005,46(5):924-926
The temperature dependence of the 35Cl NQR frequencies and spin-lattice relaxation times has been investigated for a trigonal-bipyramidal vn complex SbCl3·NH2C6H5. Thermally activated motion of chlorine atoms (pseudorotation) was not revealed in the complex, in contrast to the vπ complexes of SbCl3 with related molecular structures. The high potential barrier of pseudorotation in the aniline complex is likely to be due to the unusually high nonequivalence of Sb-Cl chemical bonds. 相似文献
20.
A solvatothermal reaction of the octahedral cluster molybdenum complex (H3O)2[Mo6(μ3-Cl)8Cl6] · 6H2O with CaCl2 · 6H2O and OPPh3 in acetonitrile gave the known polymeric complex trans-[{Ca(OPPh3)4}{Mo6(μ3-Cl)8Cl6}]∞. However, a closer examination revealed that this system also produces a novel cluster complex, [Ca(OPPh3)5][Mo6(μ3-Cl)8Cl6] · OPPh3, which was isolated and characterized by X-ray diffraction. 相似文献