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1.
The single crystal structure of NH4[UO2(CH3COO)3] (I), K[UO2(CH3COO)3] (II), and Cs[UO2(CH3COO)3] (III) is studied by X-ray diffraction. I and II crystallize in the tetragonal crystal system. The crystal data are as follows: a = 13.6985(3) and c = 27.5678(14) ?, V = 5173.1(3) ?3, space group I41/a, Z = 16, and R = 0.023 for I; a = 13.8890(5) and c = 26.0839(18) ?, V = 5031.7(4) ?3, space group I41/a, Z = 16, and R = 0.037 for II. Crystals III are orthorhombic, a = 18.176(2), b = 13.119(2), and c = 22.088(4) ?, V = 5267(1)?3, space group Pbca, Z = 16, and R = 0.0424. In structures I–III, the uranium-containing structural units are represented by discrete mononuclear [UO2(CH3COO)3] groups, which belong to the AB 301 (A = UO22+, B 01=CH3COO) crystal chemical group of uranyl complexes.  相似文献   

2.
Crystals of congruently melting K2Cd2(SO4)3 (having the langbeinite structure with a ferroelastic transition temperature of 156°C) were grown by the Bridgman and Czochralski techniques. The former yielded colorless crystals when using oxygen under pressure; the latter yielded tan crystals of slightly smaller unit cell volume and are assumed to be oxygen deficient. The ferroelastic transition was studied by thermal expansion measurements. Reexamination of the phase diagram showed the existence of a previously unreported phase K6Cd(SO4)4 which is stable only between 520°C and the melting point of about 890°C.  相似文献   

3.
Single crystals of the compound (NH4)3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) are synthesized, and their structure is investigated using X-ray diffraction. Compound I crystallizes in the monoclinic system with the unit cell parameters a = 18.3414(6) ?, b = 16.3858(7) ?, c = 12.4183(5) ?, β = 92.992(1)°, space group C2/c, Z = 4, V = 3727.1(3) ?3, and R = 0.0253. The uranium-containing structural units of crystals I are mononuclear complexes of two types with an island structure, i.e., the [UO2(CH3COO)3] anionic complexes belonging to the crystal-chemical group (AB 301 = UO22+, B 01 = CH3COO) of the uranyl complexes and the [UO2(CH3COO)(NCS)2(H2O)] anionic complexes belonging to the crystal-chemical group AB 01M31 (A = UO22+, B 01 = CH3COO, M 1 = NCS or H2O).  相似文献   

4.
The synthesis and X-ray diffraction analysis of K2(H5O2)[UO2(C2O4)2(HSeO3)] single crystals have been performed. This compound crystallizes in the triclinic system with the unit-cell parameters a = 6.7665(4) ?, b = 8.8850(4) ?, c = 12.3147(7) ?, α = 94.73°, β = 90.16°, γ = 92.11°, sp. gr. P[`1]P\bar 1, Z = 2, and R = 0.019. The basic structural units are island [UO2(C2O4)2(HSeO3)]3− groups, which belong to the AB 201 M 1 crystallochemical group of uranyl complexes (A = UO22+, B 01 = C2O42−, and M 1 = HSeO3). Uraniumcontaining complexes are linked through K+ and H5O2+ ions and via a system of hydrogen bonds with the participation of oxonium hydrogen atoms in this structure.  相似文献   

5.
6.
Nd^3+:KGd(WO4)2激光晶体的研究   总被引:5,自引:6,他引:5  
合成了一系列不同Nd  相似文献   

7.
Crystals grown from a solution of dimethylammonium and copper chlorides are studied using electron paramagnetic resonance (EPR) and X-ray diffraction. The dielectric properties of the crystals grown are measured. It is established that the crystals have the composition [(CH3)2NH2]2CuCl4[(CH3)2NH2]Cl and, in phase I at room temperature, are described by the orthorhombic space group Pna21 with the unit cell parameters a = 11.338 Å, b = 9.981 Å, and c = 15.675 Å. At temperatures of 279 K and 253 K, the crystals undergo jumpwise phase transitions into the incommensurate modulated ferroelectric phase II and commensurate modulated phase III, respectively. __________ Translated from Kristallografiya, Vol. 49, No. 1, 2004, pp. 92–100. Original Russian Text Copyright ? 2004 by Kirpichnikova, Pietraszko, Bednarski, Waplak, Sheleg. Dedicated to the 80th Birthday of L.A. Shuvalov  相似文献   

8.

Abstract  

Two neodymium thiostannates [Nd(dien)3]2[(Sn2S6)Cl2] (1) and [Nd(dien)3]2[(Sn2S6)(SH)2] (2) (dien = diethylenetriamine) were synthesized by the reaction of tin and sulfur in the presence of NdCl3 and Nd2O3, respectively under solvothermal conditions. Compounds 1 and 2 crystallize in monoclinic space group P21/n. Crystallographic data for 1: a = 11.6722(16), b = 15.119(2), c = 14.1566(19) ?, β = 96.213(3)°, V = 2483.6(6) ?3, Z = 4. For 2: a = 11.7190(14), b = 15.2168(19), c = 14.2209(18) ?, β = 95.775(4)°, V = 2523.1(5) ?3, Z = 4. The nine-coordinate [Nd(trien)3]3+ complex cation formed in situ acts as the counter ion to the [Sn2S6]4− anion. The [Nd(dien)3]3+, [Sn2S6]4− and Cl (or SH) ions form a 3-dimensional network structure through the N–H···S and N–H···Cl hydrogen bonds.  相似文献   

9.

Abstract  

Two copper coordination polymers [CuI(bipy)1/2Cl] n (1) and {[(CuII)4(phen)4(SSA)2Cl2] (H2O)2(DMF)2} n (2)(bipy = 4,4′-bipyridine, phen = 1,10-phenanthroline, H3SSA = 5-sulfosalicylic acid, DMF = N,N-dimethylformamide) have been prepared and characterized by X-ray diffraction, elemental analysis, IR spectrum and 2 was also studied by cyclic voltammetric method. X-ray analysis indicates that both of them have Cu2Cl2 bridging subunit. Complex 1 is a two dimensional network structure. While 2 shows a one dimensional zigzag chain. Electrochemistry studies reveal that complex 2 undergo a quasi reversible one-electron metal-centered redox process at E 1/2 = +0.062 V.  相似文献   

10.
Abstract  A novel binuclear Smarium (III) complex with N-(2-propionic acid)-salicyloyl hydrazone (C10H10N2O4, H3L) was prepared and characterized. The crystal structure of [Sm2(H2L)2(HL)2(H2O)4] (1) was determined by X-ray single crystal diffractometry. 1 crystallizes in the monoclinic systerm, space group P2(1)/c, with a = 0.10229(2), c = 31.549(7), b = 0.70599(15) nm, and Z = 4. In the structure, Sm(III) is nine-coordinated by carboxyl O and acyl O atoms and imido N atoms of two ligands (H2L and HL forms) and O atoms from two water molecules. H2L and HL act as tridentate ligands which form two stable five-numbered chelating rings sharing one edge in the keto form for each ligand, and the carboxyl groups of two ligands were coordinated via bidentated bridging form. The coordination polyhedron around Sm (III) was described as a monocapped square antiprism. The inter- and intramolecular hydrogen bonds resulted in a three-dimensional network and provided extra stability for the structure. The complex was researched the interaction with calf thymus DNA by electronic absorption titration and emission titration. The results show that the complex is bound to calf thymus DNA mainly by intercalation .The complex also shows good fluorescence property. Index Abstract  The title compound, [Sm2(H2L)2(HL)2(H2O)4] was synthesized by the treatment of N-(2-propionic acid)-salicyloyl hydrazone (C10H10N2O4, H3L) and Sm(NO3) · 4H2O and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that Sm (III) is nine-coordinated by carboxyl O and acyl O atoms and imido N atoms of two ligands (H2L and HL forms) and O atoms from two water molecules. The carboxyl groups of two ligands were coordinated via bidentated bridging form. The coordination polyhedron around Sm (III) was described as a monocapped square antiprism. The inter- and intramolecular hydrogen bonds resulted in a three-dimensional network and provided extra stability for the structure.   相似文献   

11.
On the basis of the physicochemical analysis of the solubility phase diagrams for the Me 2SO4-NiSO4-H2O ternary systems (Me = Na, Rb, or Cs), the optimum concentration and temperature conditions for the crystallization of the Me 2Ni(SO4)2 · nH2O solid phases were found. Techniques for growth of single crystals of these binary salts have been developed. Such techniques allow application of mother liquors containing hydrates or anhydrous sulfates of Na, Rb, Cs, and Ni as raw materials. Na2Ni(SO4)2 · 4H2O, Rb2Ni(SO4)2 · 6H2O, and Cs2Ni(SO4)2 · 6H2O single crystals (28–34) × (8–13) × (5–10) mm3 in size have been grown from aqueous solutions in the dynamic regime. Original Russian Text ? L.V. Soboleva, 2007, published in Kristallografiya, 2007, Vol. 52, No. 6, pp. 1141–1144.  相似文献   

12.
A new organic-inorganic hybrid γ-octamolybdate complex, (NH4)4[(C3H7NO)2Mo8O26]·2CH3CH2OH·2H2O was synthesized from the mixture of ethanol, DMF, 4-aminobenzoic acid, (NH4)6Mo7O24·4H2O, HCl and H2O. The structure was determined by X-ray crystallography. It crystallizes in monoclinic P21/n space group with the crystal cell parameters of a = 8.8825(4), b = 21.1608(10), c = 11.1343(6) ?, β = 104.7720(10)°, V = 2023.64(17) ?3 and Z = 2. The crystal X-ray analysis shows that two DMF molecules are bound to γ-octamolybdate anion. The molecular structure is stabilized by the complex hydrogen bonding.  相似文献   

13.
NdAl3(BO3)4 single crystals were grown by the flux method and the TSSG technique using a K2O/3MoO3/B2O3/0.5Nd2O3/KF flux system. Light-violet clear crystals could be obtained. The effects of fluoride on the growth of NAB crystals were investigated. As the content of KF was gradually increased, the growth form of NAB was changed from the equant to the columnar and the primary crystalline region of NAB was shrinked. At the ratio of KF/K2O = 0.75, NAB crystals could not be grown.  相似文献   

14.
The title compound, Cu3(Bipy)2(L1)2(L2)2⋅4H2O, was synthesized in the methanol solution of Bipy and Cu(II) in the presence of 1-((2-sulfonate-ethylimino)-methyl)-2-naphthol (L1), which was condensation compound of taurine and 2-hydroxy-1-naphthaldehyde. This complex crystallized in the space group P-1 with a = 9.825(2) ?, b = 12.626(2) ?, c = 14.342(3) ?, α = 90.29(1), β = 100.67(1), γ = 101.67(2), and Z = 2. In the trinuclear Cu(II) complex, there are two type Cu atoms which have square and square pyramid geometries, respectively. The Cu–N distances vary from 1.965(3) to 2.000(4) ?, while the Cu–O distances are between 1.896(3) and 2.337(4) ?.  相似文献   

15.
Single crystals of bis(dimethyl sulfoxide) uranyl sulfate are prepared, and their crystal structure is determined using X-ray diffraction analysis. The crystals are monoclinic, space group P21/c, a = 12.9189(8) ?, b = 7.9008(5) ?, c = 12.1405(7) ?, β = 95.677(1)°, R 1 = 0.0216, wR 2 = 0.0468 for 2761 unique reflections with F > 2σ(F). The crystal structure of the UO2SO4 · 2Dmso compound (where Dmso is dimethyl sulfoxide) is built up of infinite uncharged ribbons of the composition [UO2SO4 · 2Dmso], in which the SO4 tetrahedron is tridentately coordinated to two uranyl groups. The differences between the structures of the uranyl sulfate compounds formed upon replacement of dimethyl sulfoxide by other molecules are considered. Original Russian Text ? E.V. Alekseev, E.V. Suleĭmanov, E.V. Chuprunov, G.K. Fukin, E.V. Baranov, 2007, published in Kristallografiya, 2007, Vol. 52, No. 2, pp. 283–286.  相似文献   

16.
Barite-type α-BaBeF4 (a = 8.8594(3), b =5.3265(2), c = 7.0493(2) Å, Pnma (No. 62)) and Ba(BeF4)0.535(7)(SO4)0.465(7) (a = 8.8657(2), b = 5.3902(2), c = 7.1007(2) Å, Pnma (No. 62)) were prepared by precipitation from aqueous solutions and their structures refined from laboratory X-ray powder diffraction data. In the case of α-BaBeF4 it was possible to identify the light atom Be on a difference Fourier map and to refine its positional parameters in the presence of a heavy atom (Ba). Both phases contain almost ideal isolated BX42− tetrahedra (B = Be, Be/S and X = F, F/O) together with Ba, that is 12-fold coordinated by X. The plausibility of the resulting structures was proved with the help of the bond valence model. For both compounds no phase transitions were found up to 550C.  相似文献   

17.
Dark red crystals of bis[trans-dinitrobis(ethylenediamine)cobalt(III)] dichromate, [trans-Co(en)2(NO2)2]2(Cr2O7) have been obtained by slowly allowing to mix the solutions of potassium dichromate and trans-dinitrobis(ethylenediamine)cobalt(III) nitrate in 1:2 molar ratio in aqueous medium. Elemental analyses and spectroscopic techniques (IR, UV/visible, 1H and 13C NMR) were used for characterizing the complex salt. The complex salt crystallizes in the orthorhombic space group Fdd2 with unit cell dimensions a = 24.778(2) ?, b = 30.457(2) ?, c = 6.5364(5) ?, Z = 8, V = 4932.8(7) ?3, R1 = 0.0617 and wR2 = 0.1518. X-ray structure determination revealed an ionic structure consisting of cationic cobaltammine [trans-Co(en)2(NO2)2]NO3 and dichromate anion. It is the first crystal structure of this cation with a dianion.  相似文献   

18.
The crystal structure of the K2[(NpO2)2(CrO4)3(H2O)] · 3H2O compound was established. The structure consists of anionic layers [(NpO2)2(CrO4)3(H2O)] n 2n , between which K+ ions and crystallization water molecules are located. The coordination polyhedra of Np atoms are distorted pentagonal bipyramids. All chromate ions are bound in a tridentate-bridging fashion. __________ Translated from Kristallografiya, Vol. 49, No. 4, 2004, pp. 676–680. Original Russian Text Copyright ? 2004 by Grigor’ev, Fedoseev, Budantseva, Bessonov, Krupa.  相似文献   

19.
Uranyl triacetate complexes (Cs0.5Ba0.25)[UO2(CH3COO)3] (I) and Ba0.5[UO2(CH3COO)3] (II) are synthesized for the first time and their structures are determined by X-ray diffraction. Both compounds crystallize in the cubic crystal system. The crystal data are as follows: a = 17.3289(7) ?, V = 5203.7(4) ?3, space group I213 and Z = 16 (I); a = 17.0515(8)?, V = 4957.8(4) ?3, space group I $ \bar 4 $ \bar 4 3d, and Z = 16 (II). In I and II, as in all uranyl triacetates studied earlier, the coordination polyhedron of the uranium atom is a hexagonal bipyramid whose vertices are occupied by the oxygen atoms of the uranyl and three acetate groups. The uranium-containing group belongs to the AB 301 (A = UO22+, B 01 = CH3COO) crystal chemical group of uranyl complexes. It was found that compound II is isostructural to the (Rb0.50Ba0.25)[UO2(CH3COO)3] studied earlier.  相似文献   

20.
Single crystals of rare earth (RE) selenates of the compositions Nd(HSeO4)3, Sm(HSeO4)3, and Nd2(SeO4)3 · 5H2O are synthesized and studied by X-ray diffraction analysis at T = 297 and 180 K. It is established that Nd and Sm hydrogen selenates are isostructural to one another and to the corresponding hydrogen sulfates. Neodymium selenate pentahydrate is not isostructural to the analogous RE sulfates, although their structural motifs are similar. __________ Translated from Kristallografiya, Vol. 49, No. 5, 2004, pp. 835–840. Original Russian Text Copyright ? 2004 by Zakharov, Troyanov, Kemnitz.  相似文献   

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