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1.
Glass-formation boundaries in the Al(IO3)3-Al2(SO4)3-H2O system are determined. The IR spectra of glassy and crystalline Al(IO3)3 · 8H2O samples are measured. The structure and properties of glassy Al(IO3)3 · 10H2O are compared to those of glassy Al2(SO4)3 · 10H2O.  相似文献   

2.
Infrared and Raman Spectroscopy of the Isostructural Iodate Hydrates M(IO3)2 · 4 H2O (M = Mg, Ni, Co)-Crystal Structure of Cobalt Iodate Tetrahydrate The iodate tetrahydrates Mg(IO3)2 · 4 H2O, β-Ni(IO3)2 · 4 H2O, Co(IO3)2 · 4 H2O and their deuterated specimens were studied by X-ray, infrared and Raman spectroscopic methods. The title compounds are isostructural crystallising in the monoclinic space group P21/c (Z = 2). The crystal structure of Co(IO3)2 · 4 H2O (a = 836.8(5), b = 656.2(3), c = 850.2(5) pm and β = 100.12(5)°) has been refined by single-crystal X-ray methods (Robs = 3.08%, 693 unique reflections I0 > 2σ(I)). Isolated Co(IO3)2(H2O)4 octahedra form layers parallel (100). Within these layers, the two crystallographically different hydrate water molecules form nearly linear hydrogen bonds to adjacent IO3 ions (νOD of matrix isolated HDO of Co(IO3)2 · 4 H2O (isotopically diluted samples) 2443 (H3), 2430 (H2), and 2379 cm–1 (H1 and H4), –180 °C). Intramolecular O–H and intermolecular H…O distances were derived from the novel νOD vs. rOH and the traditional νOD vs. rH…O correlation curves, respectively. The internal modes of the iodate ions of the title compounds are discussed with respect to their coupling with the librations of the hydrate H2O molecules, the distortion of the IO3 ions, and the influence of the lattice potential.  相似文献   

3.
The solid‐liquid equilibria in the quinary system Na+, K+//Cl?, SO2?4, B4O2?7‐H2O at 298 K had been studied experimentally using the method of isothermal solution saturation. Solubilities and densities of the solution of the quinary system were measured experimentally. Based on the experimental data, the dry‐salt phase diagram and water content diagram of the quinary system were constructed, respectively. In the equilibrium diagram of the quinary system Na+, K+//Cl?, SO2?4, B4O2?7‐H2O at 298 K, there are five invariant points F1, F2, F3, F4 and F5; eleven univariant curves E1F1, E2F2, E3F3, E4F5, E5F2, E6F4, E7F5, F1F4, F2F4 F1F3 and F3F5, and seven fields of crystallization saturated with Na2B4O7 corresponding to Na2SO4, Na2SO4·10H2O, Na2SO4·3K2SO4 (Gla), K2SO4, K2B4O7·4H2O, NaCl and KCl. The experimental results show that Na2SO4·3K2SO4 (Gla), K2SO4 and K2B4O7·4H2O have bigger crystallization fields than other salts in the quinary system Na+, K+//Cl?, SO2?4, B4O2?7‐H2O at 298 K.  相似文献   

4.
H3OLa(SO4)2 · 3 H2O: A New Acidic Sulfate of the Rare Earth Elements Colorless single crystals of H3OLa(SO4)2 · 3 H2O have been obtained by the reaction of La2O3 and sulfuric acid (80% H2SO4) at 150 °C. In the crystal structure (monoclinic, P21/c, Z = 4, a = 1119.5(5), b = 693.3(2), c = 1357.4(4) pm, β = 110.94(4)°) La3+ is ninefold coordinated by oxygen atoms which belong to five SO4 ions and three H2O molecules. One of sulfate groups acts as a bidentate ligand. Hydrogen bonding is observed with H2O molecules as donors and acceptors. Furthermore, strong hydrogen bonds are formed between the H3O+ ions and oxygen atoms of the SO42– groups.  相似文献   

5.
6.
Zinc Iodates – Infrared and Raman Spectra, Crystal Structure of Zn(IO3)2 · 2 H2O The zinc iodates Zn(IO3)2 · 2 H2O and Zn(IO3)2 as well as α‐Co(IO3)2 · 2 H2O were studied by X‐ray, IR‐ and Raman spectroscopic methods. The crystal structure of the dihydrate, which is isostructural with the respective cobalt compound, was determined by X‐ray single‐crystal studies (space group P1, Z = 2, a = 490,60(4), b = 667,31(5), c = 1088,85(9) pm, α = 98,855(6), β = 91,119(7), and γ = 92,841(6)°, R1 = 2,55%, 2639 unique reflections I > 2σ(I)). Transconfigurated Zn(IO3)4(H2O)2 octahedra are threedimensionally connected via common IO3 ions parallel to [001] and hydrogen bonds parallel to [100] and [010], respectively. Anhydrous Zn(IO3)2 crystallizes in space group P21 (Z = 2) with a = 548,9(2), b = 512,4(1), c = 941,8(2) pm, and β = 90,5(3)°. The structure of Zn(IO3)2 is a monoclinically distorted variant of the structures of β‐Ni(IO3)2 (space group P63) and Co(IO3)2 (P3). The O–H … O–IO2 hydrogen bonds of the crystallographically different H2O molecules of the dihydrates (νOD (OD stretching modes of isotopically dilute samples) 2430, 2415, 2333 and 2300 cm–1, Zn(IO3)2 · 2 H2O, 90 K) are examples to the matter of fact that O … O distances are only a bad measure for the strength of hydrogen bonds. The infrared and Raman spectra as well as a group theoretical treatment are presented and discussed with respect to mutual exclusion principle (possible space groups), the strength of the hydrogen bonds and the distortion of the IO3 ions at the C1 lattice sites.  相似文献   

7.
Acidic Sulfates of Neodymium: Synthesis and Crystal Structure of (H5O2)(H3O)2Nd(SO4)3 and (H3O)2Nd(HSO4)3SO4 Light violett single crystals of (H5O2)(H3O)2 · Nd(SO4)3 are obtained by cooling of a solution prepared by dissolving neodymium oxalate in sulfuric acid (80%). According to X‐ray single crystal investigations there are H3O+ ions and H5O2+ ions present in the monoclinic structure (P21/n, Z = 4, a = 1159.9(4), b = 710.9(3), c = 1594.7(6) pm, β = 96.75(4)°, Rall = 0.0260). Nd3+ is nine‐coordinate by oxygen atoms. The same coordination number is found for Nd3+ in the crystal structure of (H3O)2Nd(HSO4)3SO4 (triclinic, P1, Z = 2, a = 910.0(1), b = 940.3(1), c = 952.6(1) pm, α = 100.14(1)°, β = 112.35(1)°, γ = 105.01(1)°, Rall = 0.0283). The compound has been prepared by the reaction of Nd2O3 with chlorosulfonic acid in the presence of air. In the crystal structure both sulfate and hydrogensulfate groups occur. In both compounds pronounced hydrogen bonding is observed.  相似文献   

8.
On Copper‐tetrahydrogen‐decaoxo‐diperiodate‐hexahydrate CuH4I2O10·6H2O: Crystal Structure, Vibrational Spectroscopy and Thermal Analysis By crystallization from a strongly acidic aqueous solution copper‐tetrahydrogen‐decaoxodiperiodate‐hexahydrate CuH4I2O10· 6H2O has been obtained. In the structure of this compound (S.G. P 21/c, Nr.14), Z = 2, a = 1060.2(2) pm, b = 551.1(1) pm, c = 1164.7(2) pm, β = 111, 49(3)°) centrosymmetric [H4I2O10]2— anions in the form of two edge sharing octahedra form layers via hydrogen bonds originating from the acidic, trans‐configurated OH groups of the anions. Raman spectra are given and analyzed with respect to the internal vibrations of the periodate anion. The dehydration of the compound takes place via CuH4I2O10·3H2O and Cu(H2IO5)2 which decomposes at 170 °C to Cu(IO3)2.  相似文献   

9.
IO2F3, originally assumed to have a trigonal bipyramidal structure, is polymeric. Mass spectra confirm the existence of molecules with molecular weights up to three times the formula weight. Chemically, IO2F3 is a strong Lewis acid and fluorine ion acceptor, thus forming the anion IO2F4 ?. With SbF5 it forms a further polymeric compound (IO2F3·SbF5) n .19F-NMR, mass, IR and Raman spectra confirm the proposed structures.  相似文献   

10.
The thermal decomposition of tribochemically activated Al2(SO4)3·xH2O was studied by TG, DTA and EMF methods. For some of the intermediate solids, X-ray diffraction and IR-spectroscopy were applied to learn more about the reaction mechanism. Thermal and EMF studies confirmed that, even after mechanical activation of Al2(SO4)3·xH2O, Al2O(SO4)2 is formed as an intermediate. Isothermal kinetic experiments demonstrated that the thermochemical sulphurization of inactivated Al2(SO4)3·xH2O has an activation energy of 102.2 kJ·mol?1 in the temperature range 850–890 K. The activation energy for activated Al2(SO4)3·xH2O in the range 850–890 K is 55.0 kJ·mol?1. The time of thermal decomposition is almost halved when Al2(SO4)3·xH2O is activated mechanically. The results permit conclusions concerning the efficiency of the tribochemical activation of Al2(SO4)3·xH2O and the chemical and kinetic mechanisms of the desulphurization process.  相似文献   

11.
On the Iodine(V, VII) Oxide I2O6 The existence of the compound I2O6 is confirmed. It has been prepared by dehydration of a solution of H5IO6 and HIO3 in 95% H2SO4 by addition of oleum. Following an earlier method the compound has also been obtained by thermal decomposition of H5IO6. I2O6 is a chemical species as concluded from its individual Raman spectrum. Diamagnetism proves the formulation as a mixed-valence iodine(V, VII) oxide. According to the vibrational spectrum the compound is nearly described as an iodyl periodate IO2+IO4?.  相似文献   

12.
The characteristic feature of the structure of the title compound, dipotassium bis(sulfito‐κS)mercurate(II) 2.25‐hydrate, is a layered arrangement parallel to (001) where each of the two independent [Hg(SO3)2]2− anions are grouped into centrosymmetric pairs and are surrounded by two K+ cations to give the overall layer composition {K2[Hg(SO3)2]2}2−. The remaining cations and the uncoordinated water molecules are situated between these layers. Within the [Hg(SO3)2]2− anions, the central Hg atoms are twofold coordinated by S atoms, with a mean Hg—S bond length of 2.384 (2) Å. The anions are slightly bent [174.26 (3) and 176.99 (3)°] due to intermolecular O...Hg interactions greater than 2.8 Å. All coordination polyhedra around the K+ cations are considerably distorted, with coordination numbers ranging from six to nine. Although the H atoms of the five water molecules (one with symmetry 2) could not be located, O...O separations between 2.80 and 2.95 Å suggest a system of medium to weak O—H...O hydrogen bonds which help to consolidate the structural set‐up. Differences and similarities between the bis(sulfito‐κS)mercurate(II) anions in the title compound and those in the related salts (NH4)2[Hg(SO3)2] and Na2[Hg(SO3)2]·H2O are discussed.  相似文献   

13.
The mixed salt Cs2[I(OH)3O3] · CsSO4(H)H5IO6 (I) was synthesized for the first time, and its structure and properties were studied by X-ray diffraction, IR and Raman spectroscopies, impedance measurements and DTA method. It crystallizes in trigonal system: a = 7.503(2) Å, c = 16.631(3) Å, space group P3, Z = 2. The crystal structure consists of octahedral IO6 and tetrahedral SO4 fragments, linked by a three-dimensional network of hydrogen bonds, and of the Cs+ ions.  相似文献   

14.
The title compound, diiron(III) trisulfate–sulfuric acid–water (1/1/28), has been prepared at temperatures between 235 and 239 K from acid solutions of Fe2(SO4)3. Studies of the compound at 100 and 200 K are reported. The analysis reveals the structural features of an alum, (H5O2)Fe(SO4)2·12H2O. The Fe(H2O)6 unit is located on a centre of inversion at (, 0, ), while the H5O2+ cation is located about an inversion centre at (, , ). The compound thus represents the first oxonium alum, although the unit cell is orthorhombic.  相似文献   

15.
Crystal Structure of Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O The crystall structures of the isostructural halates Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O were determined using X-ray single crystal data (monoclinic space group C2/c? C, Z = 4), The mean bond lengths and bond angles of the halate ions in the Ba(ClO3)2 · 1 H2O-type compounds, which correspond to those of other halates, are Cl? O, 149.0, Br? O, 165.9, I? O, 180.2 pm, ClO3?, 106.4, BrO3?, 104.0, and IO3?, 99.6°. The structure data obtained are discussed in terms of possible orientational disorder of the water molecules, strengths of the hydrogen bonds, influence of the lead ions on the structure, and site group distortion of the halate ions.  相似文献   

16.
Polysulfonylamines. CLXIII. Crystal Structures of Metal Di(methanesulfonyl)amides. 12. The Orthorhombic Double Salt Na2Cs2[(CH3SO2)2N]4·3H2O: A Three‐Dimensional Coordination Polymer Built up from Cesium‐Anion‐Water Layers and Intercalated Sodium Ions The packing arrangement of the three‐dimensional coordination polymer Na2Cs2[(MeSO2)2N]4·3H2O (orthorhombic, space group Pna21, Z′ = 1) is in some respects similar to that of the previously reported sodium‐potassium double salt Na2K2[(MeSO2)2N]4·4H2O (tetragonal, P43212, Z′ = 1/2). In the present structure, four multidentately coordinating independent anions, three independent aquo ligands and two types of cesium cation form monolayer substructures that are associated in pairs to form double layers via a Cs(1)—H2O—Cs(2) motif, thus conferring upon each Cs+ an irregular O8N2 environment drawn from two N, O‐chelating anions, two O, O‐chelating anions and two water molecules. Half of the sodium ions occupy pseudo‐inversion centres situated between the double layers and have an octahedral O6 coordination built up from four anions and two water molecules, whereas the remaining Na+ are intercalated within the double layers in a square‐pyramidal and pseudo‐C2 symmetric O5 environment provided by four anions and the water molecule of the Cs—H2O—Cs motif. The net effect is that each of the four independent anions forms bonds to two Cs+ and two Na+, two independent water molecules are involved in Cs—H2O—Na motifs, and the third water molecule acts as a μ3‐bridging ligand for two Cs+ and one Na+. The crystal cohesion is reinforced by a three‐dimensional network of conventional O—H···O=S and weak C—H···O=S/N hydrogen bonds.  相似文献   

17.
Ag9I3(SeO4)2(IO3)2 was obtained for the first time by reacting a stoichiometric mixture of Ag2O, AgI and SeO2 at elevated oxygen pressure (255 MPa) and at a temperature of 500 °C. Ag9I3(SeO4)2(IO3)2 was characterized by X‐ray powder diffraction, differential scanning calorimetry, impedance spectroscopy and single crystal structure analysis. The crystal structure was solved by direct methods (I23, Z = 8, a = 12.9584(6) Å, V = 2175.9(2) Å3 and R1 = 2.70 %). The crystal structure consists of isolated SeO4 tetrahedra and trigonal IO3 pyramids separated by Ag+ and I ions. Each four of the SeO42– and IO3 anions aggregate, forming a novel supramolecular building block, showing a hetero‐cubane like structure. According to the results of impedance measurements, Ag9I3(SeO4)2(IO3)2 is a good silver ion conductor. The compound shows an abrupt increase in the ionic conductivity in the temperature range of 115 to 147 °C, and has a silver ion conductivity of 7.1 × 10–5 Ω–1 cm–1 at 25 °C. The activation energy for silver ion conduction is 0.45 eV, in the temperature range from 25 to 115°.  相似文献   

18.
Potassium Hydrogensulfate Dihydrogensulfate, K(HSO4)(H2SO4) – Synthesis and Crystal Structure Single crystals with the composition KH3(SO4)2 have been synthesized from the system Potassium sulfate/sulfuric acid. The hitherto crystallographically not investigated compound crystallizes in the monoclinic space group P21/c (14) with the unit cell parameters a = 7.654(3), b = 11.473(5) and c = 8.643(3) Å, β = 112.43(3)°, V = 701.6 Å3, Z = 4 and Dx = 2.22 g · cm?3. The structure contains two types of tetrahedra, SO3(OH) and SO2(OH)2. These tetrahedra form tetramers via hydrogen bonds consisting of both, two SO3(OH) and two SO2(OH)2 tetrahedra. The tetramers are linked to each other via hydrogen bonds. Potassium is coordinated by 9 oxygen atoms which belong to both kinds of tetrahedra. These potassium oxygen polyhedra are connected by common faces forming chains running parallel z.  相似文献   

19.
Two new solid‐state uranium(IV) sulfate x‐hydrate complexes (where x is the total number of coordinated plus solvent waters), namely catena‐poly[[pentaaquauranium(IV)]‐di‐μ‐sulfato‐κ4O:O′] monohydrate], {[U(SO4)2(H2O)5]·H2O}n, and hexaaquabis(sulfato‐κ2O,O′)uranium(IV) dihydrate, [U(SO4)2(H2O)6]·2H2O, have been synthesized, structurally characterized by single‐crystal X‐ray diffraction and analyzed by vibrational (IR and Raman) spectroscopy. By comparing these structures with those of four other known uranium(IV) sulfate x‐hydrates, the effect of additional coordinated water molecules on their structures has been elucidated. As the number of coordinated water molecules increases, the sulfate bonds are displaced, thus changing the binding mode of the sulfate ligands to the uranium centre. As a result, uranium(IV) sulfate x‐hydrate changes from being fully crosslinked in three dimensions in the anhydrous compound, through sheet and chain linking in the tetra‐ and hexahydrates, to fully unlinked molecules in the octa‐ and nonahydrates. It can be concluded that coordinated waters play an important role in determining the structure and connectivity of UIV sulfate complexes.  相似文献   

20.
Crystal Structure and Data from Vibrational Spectra of cis-Na2[Pd(SO3)2en] · 4 H2O The compound cis-Na2[Pd(SO3)2en] · 4 H2O (en = 1,2-diaminoethane) crystallizes in the orthorhombic space group Pnma with a = 623.7(2), = 1070.9(10), c = 1989.5(30) pm and Z = 4. In the [Pd(SO3)2en]2? anions the trans-influence of the sulfite ligands manifests itself in long Pd? N bonds with short Pd? S distances. A set of Na+ ions is present in face-sharing octahedra Na(OH2)6+, forming rods [Na(OH2)6/2]+ parallel to [100]. A second set of Na+ ions is surrounded by two H2O molecules and four O atoms from SO3 ligands of two anions to form likewise octahedra with face-sharing, yielding rods [Na(OH2)2/2{(OSO2)2Pd en}2/2]? parallel to [100]. Comparatively low v(Pd? N)-frequencies reveal the trans-influence of the sulfite ligands also in the vibrational spectra.  相似文献   

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