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The room-temperature syntheses and single-crystal structures of C(4)N(2)H(12).NH(4)Cl(3).H(2)O and C(6)N(2)H(14).NH(4)Cl(3) are reported. These novel molecular perovskites contain vertex-sharing octahedral (NH(4))Cl(6) arrays which replicate the octahedral packing in the cubic (SrTiO(3)) and 2-H hexagonal (BaNiO(3)) perovskite structures, respectively. The structures are completed by doubly protonated organic cations and, for the cubic phase, water molecules. Crystal data: C(4)N(2)H(12).NH(4)Cl(3).H(2)O, M(r) = 230.56, orthorhombic, Pbcm (No. 57), a = 6.5279(13) A, b = 12.935(3) A, c = 12.849(3) A, V = 1085.0(4) A(3), Z = 4; C(6)N(2)H(14).NH(4)Cl(3), M(r) = 238.59, trigonal, Pthremacr;c1 (No. 165), a = 16.1616(2) A, c = 22.3496(4) A, V = 5055.5(2) A(3), Z = 18.  相似文献   

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The 1/2V2O5-H2C2O4/H3PO4/NH4OH system was investigated using hydrothermal techniques. Four new phases, (NH4)VOPO(4).1.5H2O (1), (NH4)0.5VOPO(4).1.5H2O (2), (NH4)2[VO(H2O)3]2[VO(H2O)][VO(PO4)2]2.3H2O (3), and (NH4)2[VO(HPO4)]2(C2O4).H2O (4), have been prepared and structurally characterized. Compounds 1 and 2 have layered structures closely related to VOPO(4).2H2O and A0.5VOPO4.yH2O (A = mono- or divalent metals), whereas 3 has a 3D open-framework structure. Compound 4 has a layered structure and contains both oxalate and phosphate anions coordinated to vanadium cations. Crystal data: (NH4)VOPO(4).1.5H2O, tetragonal (I), space group I4/mmm (No. 139), a = 6.3160(5) A, c = 13.540(2) A, Z = 4; (NH4)0.5VOPO(4).1.5H2O, monoclinic, space group P2(1)/m (No. 11), a = 6.9669(6) A, b = 17.663(2) A, c = 8.9304(8) A, beta = 105.347(1) degrees, Z = 8; (NH4)2[VO(H2O)3]2[VO(H2O)][VO(PO4)2]2.3H2O, triclinic, space group P1 (No. 2), a = 10.2523(9) A, b = 12.263(1) A, c = 12.362(1) A, alpha = 69.041(2) degrees, beta = 65.653(2) degrees, gamma = 87.789(2) degrees, Z = 2; (NH4)2[VO(HPO4)]2(C2O4).5H2O, monoclinic (C), space group C2/m (No. 12), a = 17.735(2) A, b = 6.4180(6) A, c = 22.839(2) A, beta = 102.017(2) degrees, Z = 6.  相似文献   

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The Raman and infrared spectra of solid K2(12)C2O4 x H2O are reported together with, for the first time, the corresponding Raman and infrared spectra of solid K2(13)C2O4 x H2O. Raman spectra of aqueous solutions of both isotopomers are also reported. In the solid state the oxalate anion is planar with D2h symmetry in this salt, whereas in aqueous solution the Raman spectra of the anion are best interpreted on the basis of D2d symmetry. The Raman spectra of solid (NH4)2(12)C2O4 x H2O and (NH4)2(13)C2O4 x H2O, in which the oxalate anion is twisted from planarity by 28 degrees about the CC bond, have also been recorded. Several reassignments have been made. The harmonic force field for the oxalate anion in the D2h, D2 and D2d geometries has been determined in part, and approximate values of key valence force constants determined. All the observed band wavenumbers and 12C/13C isotopic shifts are well reproduced by the force fields. The potential energy distribution of the totally symmetric normal modes of planar oxalate indicates that each mode consists of extensively mixed symmetry corrdinates and that the labels previously used for the bands seen here at 475 and 879 cm(-1) would better be described as v(CC) and deltaS(CO2), respectively, putting them in the same wavenumber order as v(NN) and deltaS(NO2) for the isoelectronic and isostructural molecule N2O4. The stretching force constants of N2O4 and planar C2O4(2-) are established to be in the order f(NN) < f(CC) and f(NO) > f(CO), consistent with the known relative bond lengths.  相似文献   

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Conclusions The authors have synthesized anilinium chloranilate (NH3C6H5)2(C6O4Cl2) (I) and acid ammonium chloranilate dihydrate NH4H5O2(C6O4C12) (II). By x-ray structural analysis they have established their crystal structures. In crystals of NH4H5O2(C6O4Cl2) they find the ion H5O 2 + with the unusual O-H-O bond length of 2.81 A. The anions of chloranilic acid in crystals (I) and (II) have equal charges but different structures.Translated from IzvestiyaAkademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 487–489, March, 1981.  相似文献   

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室温固相反应合成钼磷酸铵、钨磷酸铵纳米微粒   总被引:5,自引:1,他引:5  
采用室温固相反应法合成了钼磷酸铵、钨磷酸铵两种多金属氧酸盐纳米微粒,用元素分析确定了其分子组成。它们的结构、性质、颗粒大小、表面形状分别用IR,X-射线粉末衍射、透射电镜和热分析等手段进行了研究。结果表明:两种多金属氧酸盐都为Keggin结构,晶粒分别为34nm和32nm左右,形成纳米微粒后的两种杂多阴离子的热稳定性均明显降低。  相似文献   

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Three new strontium vanadium borophosphate compounds, (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O (Sr-VBPO1) (1), (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O (Sr-VBPO2) (2), and (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4][V2P2BO12]6 10H2O (Sr-VBPO3) (3) have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane. Compound 1 has a chain structure, whereas 2 and 3 have layered structures with different arrangements of [(NH4) [symbol: see text] [V2P2BO12]6] cluster anions within the layers. Crystal data: (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 21.552(1) A, b = 27.694(2) A, c = 20.552(1) A, beta = 113.650(1) degrees, Z = 4; (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O, monoclinic, space group I2/m (no. 12), a = 15.7618(9) A, b = 16.4821(9) A, c = 21.112(1) A, beta = 107.473(1) degrees, Z = 2; (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4] [V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 39.364(2) A, b = 14.0924(7) A, c = 25.342(1) A, beta = 121.259(1) degrees, Z = 4. The differences in the three structures arise from the different steric requirements of the amines that lead to different amine-cluster hydrogen bonds.  相似文献   

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本文报导了硫氰酸铀铣(18-冠-6)铵和硫氰酸铀酰(18-冠-6)钾两种固体配合物的合成。由测定其物理常数及谱学数据, 确定了配合物的组成为[(C12H24O6)M]2UO2(NCS)4H2O(M=NH4, K)。X射线结构分析确定了二种单晶的结构。铵配合物属正交晶素, 空间群为Fdd2, 钾配合物属单斜晶系, 空间群为C2/c。  相似文献   

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A novel polymer (NH4)6[Ce(H2W12O40)(C4H2O4)(NO3)(H2O)3] ( 1 ) has been constructed at room temperature and characterized by single crystal X‐ray structural analyses, elemental analyses, cyclic voltammetry, IR spectrum, and thermogravimetry. X‐ray structural analysis reveals that through the W–Ot′–Ce–Ob–W linkages a one‐dimension infinitely linear chain with alternating cations and anions is formed. 1 represents the first characterized compound that the Ce3+ ions are coordinated by four different types of ligands, and maleinate as ligands in constructing LnPOM architecture.  相似文献   

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A planar structure of an anion cluster I- x (H2O)6 in a 3D supramolecular complex [Ru(bpy)3]2[I x (H2O)6Fe(CN)6 x H2O] has been determined by single-crystal X-ray analysis. In the supramolecule, the anion cluster I- x (H2O)6, together with the anion [Fe(CN)6 x H2O]2-, acts as a 3D crystal host, and the [Ru(bpy)3]2+ cations, as the guest molecules, occupy the vacancies of the 3D host framework. This is the first crystal example of the anion cluster I- x (H2O)6.  相似文献   

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A hydrothermal approach employing an amine as reducing agent enables synthesis of an analogue of the arsenato(iii)-oxovanadate {V(15)As(6)}, representing the first systematic variation of this intensely studied magnetic system.  相似文献   

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在水热的条件下合成了多钒硼酸盐(enH2)4Na4H3[(VO)12O6B18O42]8H2O, 化学式为C8H59B18N8Na4O68V12 (Mr=2253.45), 用单晶X射线衍射方法测定了它的结构, 该晶体属单斜晶系, P21/n空间群, 晶胞参数为a = 13.8989(4), b = 16.1954(5), c = 14.4520(4) ?β = 94.7490(5), V= 3241.95(16) ?, Z = 2, Dc = 2.308 g/cm3, ?= 1.819mm-1, F(000) = 2234, 4798个可观察衍射点(I > 2s(I)), 最终结构精修到偏离因子R = 0.0449, wR = 0.1163, S = 0.996。在该化合物的结构中, V12B18簇是由环状的B18O42通过18个B(μ3-O)V键被2个V6O18环夹在中间组成的, V12B18簇通过4个Na+与相邻的簇相连, 形成二维网状结构, 孔道尺寸为6.109×10.562 拧?  相似文献   

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The compounds (NMe4)5[As2Mo8V4AsO40] · 3 H2O 2a , (NH4)21[H3Mo57V6(NO)6O183(H2O)18] · 65 H2O 3a , (NH2Me2)18(NH4)6[Mo57V6(NO)6O183(H2O)18] · 14 H2O 3b and (NH4)12[Mo36(NO)4O108(H2O)16] · 33 H2O 4a ( 3a and 4a were not correctly reported in the literature regarding to their composition, structures and the oxidation states of the metal centres) which contain large isolated anionic species, have been prepared (among them 3a, 3b , and 4a in rather high yield) and characterized by complete crystal structure analysis as well as IR/Raman, UV/VIS/NIR, ESR spectroscopy and magnetic susceptibility measurements, redox titrations, bond valence sum calculations, elemental analyses and thermogravimetric studies. Perspectives for polyoxometalate chemistry referring to the synthesis of “extremely” large nanoscaled species are discussed, together with the occurrence of a large transferable {Mo17} building block in the compounds 3a, 3b and 4a which also exists in the corresponding iron compound Na3(NH4)12[H15Mo57Fe6(NO)6O183(H2O)18] · 76 H2O 7a .  相似文献   

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