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1.
Aqueous solutions of La(CH3CO2)3, NaCH3CO2 and La(ClO4)3 were studied using Raman spectroscopy. In dilute NaCH3CO2 solution, acetate is fully hydrated and forms only minor amounts of ion pairs. The characteristic Raman bands are discussed and assigned. In fairly dilute La(ClO4)3 solutions, the La3+(aq) ion occurs as the nonahydrate. The separation of the carboxylate bands, νas – νs (Δ-value), in NaCH3CO2(cr) compared to La(CH3CO2)3·1.5H2O(cr) correlates with the bonding type of acetate which is “ionic” in the former but bidentate chelating/tridentate chelating in the latter. Other acetate bands such as the deformation mode of the CO2 moiety, δ CO2, and the two rocking vibrations (ρ), as well as the C–C stretch show marked differences in their band positions in NaCH3CO2(cr) compared to the ones in La(CH3CO2)3·1.5H2O(aq). In a ternary solution of La(CH3CO2)3/LaCl3 with a molar ratio La3+(aq): \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \)(aq) = 3.87: 1.00), the bands of the bound acetate on La3+ were characterized and compared to those of fully hydrated acetate, \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \left( {\text{aq}} \right) \). In this solution, almost all acetate is ligated to La3+ in a bidentate fashion and two complex species could be identified (molar ratios La3+: \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \) = 1:1 and 1:2, respectively). In La(CH3CO2)3 solutions in H2O and D2O strong acetato complexes are formed and the bands of the bound acetate were characterized and compared with the ones of the fully hydrated acetate modes. A dilution series down to 0.0037 mol·L?1 in La(CH3CO2)3(aq) and to 0.0150 mol·L?1 in La(CH3CO2)3(D2O) showed that two acetate complexes are formed in these solutions. Again, it was shown that in these solutions the bound acetates on La3+ exist as bidentate ligands. DFT frequencies of the acetate on clusters {La(OH2)7O2CCH3)}2+ and {La(OH2)5(O2CCH3)2}+ compared well with the measured values. By determining the ligation number, \( \bar{n} \), it can be established that in dilute solutions, below 0.04 mol·L?1, a complex with a 1:1 stoichiometry (La3+: \( {\text{CH}}_{3} {\text{CO}}_{2}^{ - } \)) exists in equilibrium with “free” acetate while in more concentrated solutions a 1:2 complex also forms. La3+(aq) hydrolysis is slight and very small equilibrium concentrations of CH3COOH were detected (C–C stretch at 893 cm?1). From quantitative Raman measurements, K 1 was determined to be 160 ± 10 at 22 °C. 相似文献
2.
The glass formation in the Al2(SO4)3–(CH3)2SO–H2O system was found for the first time. The competitive ability of ligands, dimethyl sulfoxide and water (which are strong donors), for entering the first coordination sphere of aluminum is considered. The possibility of mixed coordination of (CH3)2SO (via sulfur and oxygen atoms) in the first coordination sphere of aluminum with retention of the glass-forming ability of the sample was suggested on the basis of IR spectral study. 相似文献
3.
A. S. Ulikhin N. F. Uvarov K. B. Gerasimov A. A. Iskakova Yu. G. Mateishina 《Russian Journal of Electrochemistry》2017,53(8):834-837
Composite solid electrolytes were synthesized from the organic salt dimethylammonium chloride (1–x)C2H8NCl–xAl2O3. Their physicochemical properties were studied. In the starting C2H8NCl salt, there is a phase transition at 39°C accompanied by an increase in conductivity by two orders of magnitude. The conductivity of the high-temperature phase is 9.3 × 10–6 S/cm at 160°C. A differential scanning calorimetry study showed that the salt in the composites spreads over the oxide surface and at x > 0.6 the salt melting enthalpy decreases to zero. The conductivity of the resulting composites was studied by impedance spectroscopy. It was shown that heterogeneous doping leads to a sharp increase in ion conductivity to 7.0 × 10–3 S/cm at 160°C and a decrease in the activation energy to 0.55 eV. 相似文献
4.
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
5.
S. P. Khranenko N. V. Kuratieva I. V. Korolkov S. A. Gromilov 《Journal of Structural Chemistry》2016,57(3):625-627
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) Å3, 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–Nav is 1.91 Å) and three oxygen atoms belonging to hydroxyl groups (Co–Oav is 1.93 Å). The hydroxyl groups act as μ3-bridges between the metal atoms. The geometric characteristics are analyzed and the packing motif is determined. 相似文献
6.
N. G. Chernorukov O. V. Nipruk A. V. Knyazev Yu. P. Pykhova 《Russian Journal of Inorganic Chemistry》2011,56(2):163-167
A method for producing synthetic troegerite of composition(UO2)3(AsO4)2 · 12H2. Owas developed. X-ray diffraction, IR spectrometry, X-ray fluorescence analysis, and scanning calorimetry were used to study
its dehydration and thermal decomposition, to solve the structgure, and to determine X-ray diffraction and IR spectroscopic
characteristics. 相似文献
7.
E. L. Tikhonova I. A. Grishin A. V. Budruev A. M. Ilyutina D. V. Lyakaev A. V. Markin 《Russian Journal of Applied Chemistry》2018,91(1):9-11
It is suggested to use sodium hexametaphosphate as a new glass-forming agent for tellurite glasses. The limits of the glass-forming region were determined for the TeO2–(NaPO3)6 system, and a selective study of the thermal behavior of the glasses synthesized was carried out by the method differential scanning calorimetry. The optical transmission in the UV, visible, and IR spectral ranges was examined. It was shown that oxides of rare-earth elements can be introduced into the glass, which opens up prospects for application of the system as a matrix for generation of laser light in the 2-μm range, required in fabrication of medical lasers. 相似文献
8.
E. A. Il’inchik T. M. Polyanskaya K. G. Myakishev 《Russian Journal of General Chemistry》2007,77(7):1148-1154
The structure of tri-μ2-disulfido-μ3-thiotris(diethyldithiocarbamato)-S,S′-triangle-trimolybdenum iodide [Mo3(μ3-S)(μ2-S2)3(Et2NCS2)3]I was determined. The compound was characterized by differential thermal analysis and IR, Raman, and X-ray electronic spectroscopy. 相似文献
9.
L. A. Zemnukhova R. L. Davidovich A. A. Udovenko E. V. Kovaleva 《Russian Journal of Coordination Chemistry》2005,31(2):115-120
Preparative method in combination with X-ray diffraction and IR spectroscopy is used to study reaction of Sb(III) fluoride with -aminoisovaleric acid (DL-valine) in an aqueous solution in the range of the molar ratios of components (0.25–2) : 1 in the presence of hydrofluoric acid. The molecular complex of Sb(III) fluoride with valine (1 : 1) of the composition SbF3{(CH3)2CHCH(+NH3)COO–}(I) and valinium tetrafluoro-antimonate(III) monohydrate {(CH3)2CHCH(+NH3)COOH}SbF4· H2O (II) are synthesized for the first time. Crystal structure was determined for the molecular complex I consisting of SbF3 groups and valine molecules united into polymer chains through bidentate bridging carboxylate groups of amino acid molecules.Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 2, 2005, pp. 125–131.Original Russian Text Copyright © 2005 by Zemnukhova, Davidovich, Udovenko, Kovaleva. 相似文献
10.
The synthesis of new compounds based on Bi2O3 is investigated because they can be used as new ecological inorganic pigments. Chemical compounds of the (Bi2O3)1−x(Y2O3)x type were synthesized. The host lattice of these pigments is Bi2O3 that is doped by Y3+ ions. The incorporation of doped ions provides the interesting colours and contributes to a growth of the thermal stability
of these compounds. The simultaneous TG-DTA measurements were used for determination of the temperature region of the pigment
formation and thermal stability of pigments. This paper also contains the results of the pigment characterization by X-ray
powder diffraction and their colour properties. 相似文献
11.
Monika Bosacka Anna Błońska-Tabero Elżbieta Filipek Jana Luxova Petra Šulcová 《Journal of Thermal Analysis and Calorimetry》2017,130(1):95-101
A new dichromium(III) cobalt(II) diphosphate(V) of the formula CoCr2(P2O7)2 was detected in the Co3Cr4(PO4)6–Cr(PO3)3 system. The new compound was obtained as a result of high-temperature solid-state reactions between CoCO3, Cr2O3 and (NH4)2HPO4 as well as between Cr(PO3)3 and Co3Cr4(PO4)6. CoCr2(P2O7)2 was characterized using XRD, DTA and IR methods. Results demonstrated that CoCr2(P2O7)2 crystallizes in the triclinic system and its unit cell parameters were calculated. Its infrared spectrum was presented. CoCr2(P2O7)2 melts incongruently at 1270±10 °C with a formation of solid α-CrPO4. The compound Co3Cr4(PO4)6, component of the system under study, was obtained for the first time as a pure phase. Its thermal stability was also investigated. Co3Cr4(PO4)6 is stable in air up to 1410 ± 20 °C. 相似文献
12.
G. B. Andreev M. Yu. Antipin N. A. Budantseva N. N. Krot 《Russian Journal of Coordination Chemistry》2005,31(11):800-803
A new neptunium(V) complex [(NpO2)2(CH3COO)2(H2O)] ? 2H2O was synthesized and its crystal structure was determined. The unit cell parameters are: a = 24.007(10) Å, b = 6.779(3) Å, c = 8.076(3) Å, space group Pnma, Z = 4, V = 1314.2(9) Å3, R = 0.049, wR(F2) = 0.105. The crystal structure of the compound is composed of neutral [(NpO2)2(CH3COO)2(H2O)] layers and molecules of the water of crystallization. Each of the crystallographically independent neptunoyl ions performs a bidentate function thus forming a composite system of cation-cation bonds. 相似文献
13.
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
14.
E. V. Makotchenko E. A. Bykova E. Yu. Semitut Yu. V. Shubin P. V. Snytnikov P. E. Plyusnin 《Journal of Structural Chemistry》2011,52(5):924-929
The crystal structure of a double complex salt of the composition [Au(en)2]2[Cu(C2O4)2]3·8H2O (en = ethylenediamine) at 150 K is determined by single crystal X-ray diffraction. The crystal data for C20H48Au2Cu3N8O32 are: a = 9.1761(3) Å, b = 16.9749(6) Å, c = 13.4475(5) Å, β = 104.333(1)°, V = 2029.43(12) Å3, P21/c space group, Z = 2, d x = 2.450 g/cm3. It is demonstrated that the thermal decomposition of the double complex salt in a helium or hydrogen atmosphere affords the solid solution Au0.4Cu0.6. 相似文献
15.
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
16.
I. V. Medrish E. V. Peresypkina A. V. Virovets L. B. Serezhkina 《Russian Journal of Coordination Chemistry》2008,34(8):629-634
The single crystals of Rb2[(UO2)2(C2O4)2(SeO4)] · 1.33H2O were synthesized and studied by X-ray diffraction. The crystals are monoclinic, space group P21/m, Z= 2, the unit cell parameters: a = 5.6537(8), b = 18.736(3), c = 9.4535(15) Å, β = 98.440(5)°, V = 990.6(3) Å3, R 1 = 0.0506. The main structural units of the crystal are infinite layers of [(UO2)2(C2O4)2(SeO4)]2?, corresponding to the crystal chemical group A2K 2 02 B2 (A = UO 2 2+ , K02 = C2O 4 2? , B2 = SeO 4 2? ) of uranyl complexes. The uranium-containing layers are united into a three-dimensional framework through the electrostatic interactions with the outer-sphere rubidium ions and the hydrogen bonding system involving the outer-sphere water molecules. 相似文献
17.
The 40-step extraction process to separate rare earth elements (RЕEs) according to the praseodymium–cerium line with the use of mixer–settler extractors in a 100% TBP–Ln(NO3)3–Ca(NO3)2 system is implemented. A lanthanum–cerium concentrate containing less than 0.03 wt % of the remaining REEs is obtained. The flow diagram of the separation process of a rare earth (RE) concentrate isolated from phosphogypsum is considered. 相似文献
18.
The optimal configurations, energy parameters, and normal vibrational frequencies of hydrates of the acetic acid molecule and anion (CH3COOH·(H2O) n (n = 1-10) and CH3CO2??(H2O) n (n = 1-8, 16)) are calculated by density functional theory (B3LYP/6-31++G(d,p)). The comparison of the calculation results with the known experimental data (Raman, NMR, and so on) gives arguments in favor of the existence of two stable heteroassociates (HAs) in СН3СООН–H2O solutions: previously found CH3COOH·(H2O)2 heterotrimer and CH3COOH·(H2O)8, and three complexes (CH3CO2??(H2O)2, CH3CO2??(H2O)6, and CH3CO2??(H2O)16) in NaCH3CO2?–H2O solutions. Each of them is most stable in a series of isomers, contains unstrained H bonds, and is characterized by the maximum molecular packing density among HAs with similar n values. The structure of the subsequent complex formed in solution uniquely follows the structure of the preceding complex and is based on it. 相似文献
19.
Ray L. Frost Sara J. Palmer Ross E. Pogson 《Journal of Thermal Analysis and Calorimetry》2012,107(3):905-909
Thermogravimetry combined with evolved gas mass spectrometry has been used to characterise the mineral crandallite CaAl3(PO4)2(OH)5·(H2O) and to ascertain the thermal stability of this ‘cave’ mineral. X-ray diffraction proves the presence of the mineral and
identifies the products of the thermal decomposition. The mineral crandallite is formed through the reaction of calcite with
bat guano. Thermal analysis shows that the mineral starts to decompose through dehydration at low temperatures at around 139 °C
and the dehydroxylation occurs over the temperature range 200–700 °C with loss of the OH units. The critical temperature for
OH loss is around 416 °C and above this temperature the mineral structure is altered. Some minor loss of carbonate impurity
occurs at 788 °C. This study shows the mineral is unstable above 139 °C. This temperature is well above the temperature in
the caves of 15 °C maximum. A chemical reaction for the synthesis of crandallite is offered and the mechanism for the thermal
decomposition is given. 相似文献
20.
P. Melnikov I. V. Arkhangelsky V. A. Nascimento L. C. S. de Oliveira W. Rodrigues Guimarães L. Z. Zanoni 《Journal of Thermal Analysis and Calorimetry》2018,133(2):929-934
The hexahydrate of praseodymium nitrate hexahydrate Pr(NO3)3·6H2O does not show phase transitions in the range of 233–328 K when the compound melts in its own water of crystallization. It is suggested that the thermal decomposition is a complex step-wise process, which involves the condensation of 6 mol of the initial monomer Pr(NO3)3·6H2O into a cyclic cluster 6[Pr(NO3)3·6H2O]. This hexamer gradually loses water and nitric acid, and a series of intermediate amorphous oxynitrates is formed. The removal of 68% HNO3–32% H2O azeotrope is essentially a continuous process occurring in the liquid phase. At higher temperatures, oxynitrates undergo thermal degradation and lose water, nitrogen dioxide and oxygen, leaving behind normal praseodymium oxide Pr2O3. The latter absorbs approximately 1 mol of atomic oxygen from N2O5 disproportionation, giving rise to the non-stoichiometric higher oxide Pr2O3.33. All mass losses are satisfactorily accounted for under the proposed scheme of thermal decomposition. 相似文献