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1.
2.
The two most metal-rich lanthanide antimony phases known were obtained from high-temperature solid state syntheses, that for Tm3Sb being of greater difficulty because of its apparent incongruent melting. The Tm3Sb phase crystallizes in the tetragonal space group P42/n (No. 86) with a Ti3P-type (Pearson: tP32) structure, a = 12.2294(5) Angstrom, c = 5.9852(5) Angstrom, and Z = 8. The phase Lu7Sb3 exhibits a Sc7As3-type tetragonal structure, I4/mcm (No. 140) (tI56), with a = 15.5974(7) Angstrom, c = 8.8130(7) Angstrom, and Z = 8. Both structures are described in terms of compact arrays of condensed chains of metal polyhedra (tetrahedral, tetrahedral star, trigonal prismatic, cubic) together with six- to nine-coordinate Sb in metal polyhedra. Magnetic susceptibility data on the paramagnetic Tm3Sb are also reported.  相似文献   

3.
The hydrothermal reaction of MoO(3) with BaH(3)IO(6) at 180 degrees C for 3 days results in the formation of Ba[(MoO(2))(6)(IO(4))(2)O(4)] x H(2)O (1). Under similar conditions, the reaction of Ba(OH)(2) x 8H(2)O with MoO(3) and Ba(IO(4))(2) x 6H(2)O yields Ba(3)[(MoO(2))(2)(IO(6))(2)] x 2H(2)O (2). The structure of 1, determined by single-crystal X-ray diffraction, consists of corner- and edge-sharing distorted MoO(6) octahedra that create two-dimensional slabs. Contained within this molybdenum oxide framework are approximately C(2v) tetraoxoiodate(V) anions, IO(4)(3-), that are involved in bonding with five Mo(VI) centers. The two equatorial oxygen atoms of the IO(4)(3-) anion chelate a single Mo(VI) center, whereas the axial atoms are mu(3)-oxo groups and complete the octahedra of four MoO(6) units. The coordination of the tetraoxoiodate(V) anion to these five highly electropositive centers is probably responsible for stabilizing the substantial anionic charge of this anion. The Ba(2+) cations separate the layers from one another and form long ionic contacts with neighboring oxygen atoms and a water molecule. Compound 2 also contains distorted MoO(6) octahedra. However, these solely edge-share with octahedral hexaoxoiodate(VII), IO(6)(5-), anions to form zigzagging one-dimensional, (1)(infinity)[(MoO(2))(IO(6))](3-), chains that are polar. These chains are separated from one another by Ba(2+) cations that are coordinated by additional water molecules. Bond valence sums for the iodine atoms in 1 and 2 are 5.01 and 7.03, respectively. Crystallographic data: 1, monoclinic, space group C2/c, a = 13.584(1) A, b = 7.3977(7) A, c = 20.736(2) A, beta = 108.244(2) degrees, Z = 4; 2, orthorhombic, space group Fdd2, a = 13.356(7) A, b = 45.54(2) A, c = 4.867(3) A, Z = 8.  相似文献   

4.
The preparation of copper-tetrasodium trimetaphosphate tetrahydrate: Na4Cu(P3O9)2 · 4H2O is described. This salt is the first example of the occurence of CuII in a trimetaphosphate. The triclinic unit cell has the dimensions a = 7.907(5), b = 8.364(5), c = 7.122(5) Å, α = 102.46(5), β = 97.89(5), γ = 84.04(5)°. Crystal structure has been solved by using 2019 independent reflexions with a final R value 0.017. Both copper and sodium atoms are in octahedral coordination. NaO6 octahedra form ribbons running in (011) planes. These ribbons are interconnected by CuO6 octahedra as to form a three dimensional network. Hydrogen atoms have been located and refined. The hydrogen bond scheme is described.  相似文献   

5.
Several rare‐earth cyclotriphosphate hydrates were obtained from mixtures of sodium cyclotriphosphates and the respective rare‐earth chlorides. Nd(P3O9) · 3H2O [P$\bar{6}$ , Z = 3, a = 677.90(9), c = 608.67(9) pm, R1 = 0.016, wR2 = 0.038, 312 data, 36 parameters] was obtained by a solid state reaction and is isotypic with respective rare‐earth phosphate hydrates, while all the others adopt new structure types. Nd(P3O9) · 4.5H2O [C2/c, Z = 8, a = 1644.6(3), b = 756.11(15), c = 1856.1(4) pm, β = 97.25(3)°, R1 = 0.032, wR2 = 0.081, 1763 data, 194 parameters], Nd(P3O9) · 5H2O [P21/c, Z = 4, a = 773.75(15), b = 1149.1(2), c = 1394.9(3) pm, β = 106.07(3)°, R1 = 0.042, wR2 = 0.082, 1338 data, 194 parameters], Pr(P3O9) · 5H2O [P$\bar{1}$ , Z = 2, a = 745.64(15), b = 889.07(18), c = 934.55(19) pm, α = 79.00(3), β = 80.25(3), γ = 66.48(3), R1 = 0.059, wR2 = 0.089, 1468 data, 193 parameters], Na3Nd(P3O9)2 · 6H2O [P21/n, Z = 4, a = 1059.78(18), b = 1207.25(15), c = 1645.7(4) pm, β = 99.742(17), R1 = 0.047, wR2 = 0.119, 1109 data, 351 parameters] and Na3Pr(P3O9)2 · 6H2O [P21/n, Z = 4, a = 1061.42(16), b = 1209.0(2), c = 1635.5(3) pm, β = 99.841(13), R1 = 0.035, wR2 = 0.062, 1323 data, 350 parameters] were obtained by careful crystallization at room temperature. A thorough structure discussion is given. The infrared spectrum of Nd(P3O9) · 4.5H2O is also reported.  相似文献   

6.
Dicaesium divanadium trioxide phosphate hydrogenphosphate, Cs2V2O3(PO4)(HPO4), (I), and dicaesium tris[oxidovanadate(IV)] hydrogenphosphate dihydrate, Cs2[(VO)3(HPO4)4(H2O)]·H2O, (II), crystallize in the monoclinic system with all atoms in general positions. The structures of the two compounds are built up from VO6 octahedra and PO4 tetrahedra. In (I), infinite chains of corner‐sharing VO6 octahedra are connected to V2O10 dimers by phosphate and hydrogenphosphate groups, while in (II) three vanadium octahedra share vertices leading to V3O15(H2O) trimers separated by hydrogenphosphate groups. Both structures show three‐dimensional frameworks with tunnels in which Cs+ cations are located.  相似文献   

7.
Crystal structures of (Et4N)2[Mo3S7Br6] (I) and (Et4N)(H9O4)[Mo3S7Cl6] (II) clusters belonging to the class of Mo3S 7 4+ were determined by X-ray diffraction analysis. Crystals I are orthorhombic a=19.106(3), b=12.930(2), c=29.887(5) Å, V=7383(2) Å3, space group Pbca, Z=8, dcalc=2.253 g/cm3, R(F)=0.0402, wR(F2)=0.0587 for 2493 Fhkl>4σ. Crystals II are monoclinic, a=17.106(3), b=18.882(4), c=11.006(2), Å, β=126.13(3)°, V=2871.2(9) Å3, space group Cc, Z=4, dcalc=2.147 g/cm3, R(F)=0.0181, wR(F2)=0.0445 for 2307 Fhkl>4σ. Structure I has an anion dimer with 3Sax…Cl=3.258(4)–3.404(4) Å; the dimer is similar to that observed in the structures of A2[M3X7Hal6], A=Ph4P+, Ph3EtP+, and PPN+. In structure II, infinite chains of anions bonded by 3Sax…Cl contacts of 3.183(3)–3.394(3) Å were found. A similar phenomenon was established earlier for the structure of (Et4N)(H9O4)[Mo3S7Br6] (III), which is not isostructural to II. Compounds II and III also differ in the structure of the H9O4 + cation: infinite helix in II and pyramid in III.  相似文献   

8.
Four new metal iodates, beta-Cs2I4O11, Rb2I6O15(OH)2.H2O, La(IO3)3, and NaYI4O12, have been synthesized hydrothermally, and the structures were determined by single-crystal X-ray diffraction techniques. All of the reported materials contain I5+ cations that are in asymmetric coordination environments attributable to their stereoactive lone pair. Second-order nonlinear optical measurements on noncentrosymmetric La(IO3)3 and NaYI4O12, using 1064-nm radiation, indicate that both materials have second-harmonic-generating properties with efficiencies of approximately 400xSiO2. Converse piezoelectric measurements revealed d33 values of 5 and 138 pm V-1 for La(IO3)3 and NaYI4O12, respectively. Infrared and Raman spectroscopy and thermogravimetric analyses are also presented for all of the reported materials. Crystal data: beta-Cs2I4O11, monoclinic, space group P2(1)/n (No. 14), with a=12.7662(14) A, b=7.4598(8) A, c=14.4044(16) A, beta=106.993(2) degrees, V=1311.9(2) A3, and Z=4; Rb2I6O15(OH)2.H2O, triclinic, space group P (No. 2), with a=7.0652(17) A, b=7.5066(18) A, c=18.262(4) A, alpha=79.679(4) degrees, beta=85.185(4) degrees, gamma=70.684(4) degrees, V=898.9(4) A3, and Z=2; La(IO3)3, monoclinic, space group Cc (No. 9), with a=12.526(2) A, b=7.0939(9) A, c=27.823(4) A, beta=101.975(4) degrees, V=2418.4(6) A3, and Z=4; NaYI4O12, monoclinic, space group Cc (No. 9), with a=31.235(3) A, b=5.5679(5) A, c=12.5451(12) A, beta=91.120(3) degrees, V=2181.3(4) A3, and Z=4.  相似文献   

9.
在半水溶剂热条件下,采用不同的合成条件合成了两个锗酸盐微孔分子筛:( H_3单晶结构解析表明,两个晶体结构具有相同的"火箭状"二级结构单元(SBU), SBU的不同的连接方式导致了完全不间结构.H_4Ge_7O_(16)·7H_2O的结晶学数据 为M_r=894 .27,Pλ=O.071073nm,R(F)=3.48%,wR(F~2)=8.39%. K_4Ge_9O_(20)的结晶学数据为C=0.7383(2)nm,V=16618(7)nm~3,Z=4,Mo Ka,R(F)=3.92%,wR(F~2)=11.97%.  相似文献   

10.
11.
Molecular and Crystal Structures of (CO)4W(μ-S-t-C4H9)2W(CO)4, η7-C7H7W(μ-SC6H4CH3)3W(CO)3 and η7-C7H7W(μ-S-n-C4H9)3W(CO)(μ-S-n-C4H9)2W(CO)4 The molecular structures of the two binuclear complexes (CO)4W(μ-S-t-C4H9)2W(CO)4 and η7-C7H7W(μ-SC6H4CH3)3W(CO)3 and of the tungsten cluster η7-C7H7W(μ-S-n-C4H9)3W(CO)-(μ-S-n-C4H9)2W(CO)4 respectively are described. In the nonlinear trinuclear cluster the central tungsten atom is connected to the two tungsten atoms by two and three μ-S-n-C4H9 bridges respectively and additionally by one W? W bond each. The coordination sphere of the W atoms is completed by a η7-C7H7 ring and four CO groups respectively; the central tungsten carries an additional CO group.  相似文献   

12.
The structure of the title compound, potassium trinickel arsenate diarsenate, is built up from corner‐ and edge‐sharing NiO6 octahedra, AsO4 tetrahedra and As2O7 groups, giving rise to a polyhedral connectivity which produces large tunnels running along the crystallographic [010] direction. The K+ cations are located within these tunnels.  相似文献   

13.
Te(OH)6 · 2Na3P3O9 · 6H2O, is hexagonal (P63/m) with a = 11,67(1), c = 12,12(1) Å, Z = 2 and Dx = 2,225 g/cm3. Te(OH)6 · K3P3O9 · 2H2O, is monoklin (P21/c) with a = 19,61(5), b = 7,456(1), c = 14,84(6) Å, = 108,01(4), Z = 4 and Dx = 2,506 g/cm3. Both compounds are the first examples of phosphate tellurates in which the anion phosphate is condensed to the ring anion P3O9. As in phosphate tellurates already described the phosphate groups are independent of the TeO6 octahedra.  相似文献   

14.
Double-Octahedra Clusters [V2O9] in the Crystal Structure of Vanadium (III) Diphosphate, V4(P2O7)3 . As the first example for MIII diphosphates the crystal structure of V4(P2O7)3 (“ I ”) has been determined by means of X-ray diffraction of single crystals. I – according to [7] obtainable by thermal interaction of V2O5, H3PO3, and H3PO4 – crystallizes orthorhombically (data see above); in the unit cell two kinds of isolated doubleoctahedra (clusters) [V2O9], having the symmetry Cs, exist. Due to a mutual face-connection of the octahedra, within these clusters relatively short V–V distances are resulting: 2.774(8) and 3.026(7) Å. The diphosphate anions, O3POPO34? (three kinds; each having the symmetry Cs and staggered conformation), exhibit POP bond angles of 170°, being remarkably large for non-centrosymmetry. Because of the [M2IIIO9] clusters in I , and also in the isostructural diphosphates Cr4(P2O7)3 and Fe4(P2O73), magnetic investigations seem to be challenged.  相似文献   

15.
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   

16.
17.
A new microporous zirconogermanate, di­ammonium zirconium trigermanate, (NH4)2ZrGe3O9 (FDZG‐2), analogous to wadeite (K2ZrSi3O9), was hydro­thermally synthesized using ZrO(NO3)2·2H2O as the source of zirconium and 1,4‐di­amino­butane as a structure‐directing agent. Single‐crystal X‐ray diffraction analysis reveals that the framework structure is built up of cyclic trigermanate units crosslinked by ZrO6 octahedra. The Zr atom lies at a site with symmetry and the unique N atom of the ammonium ion lies at a site with threefold symmetry. Large cages are observed, with two NH4+ cations in each. The structure contains intersecting six‐ and three‐membered ring (6MR and 3MR) channels, but only the 6MR channels can accommodate the NH4+ ions.  相似文献   

18.
Hsu KF  Wang SL 《Inorganic chemistry》2000,39(8):1773-1778
A new manganese gallium phosphate, Mn3(H2O)6Ga4(PO4)6, has been synthesized under hydrothermal conditions at 150 degrees C and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, magnetic susceptibility, and electron paramagnetic resonance (EPR) spectroscopy. It crystallized in the monoclinic space group, P2(1)/n, with a = 8.9468(4) A, b = 10.148(5) A, c = 13.5540(7) A, beta = 108.249(1) degrees, and Z = 2. The compound is unusual in that it is not only the first nonoranically templated MnGaPO phase but also the first instance where edge-shared trinuclear manganese-oxygen clusters are encapsulated in a metal phosphate lattice. The trimer involves a central Mn(H2O)4O2 octahedron, which links to two Mn (H2O)2O4 octahedra at trans edges. The Mn3(H2O)6O8 clusters reside in tunnels built from GaO5 trigonal bipyramids and PO4 tetrahedra. Our magnetic study revealed that superexchange interactions occurred between the neighboring MnII centers. A good fit of the magnetic susceptibility data for the isolated trimers was obtained by using a derived expression based on Van Vleck's equation. Unlike all existing linear trinuclear MnII complexes, the chi MT product in the range 8-4 K remains at a constant value corresponding to one spin S = 5/2 per three MnII centers. The Curie behavior at such low temperatures has been confirmed by EPR data. According to the thermogravimetric analysis/differential thermal analysis (TGA/DTA) results, the title compound is thermally stable up to ca. 200 degrees C.  相似文献   

19.
《Solid State Sciences》2001,3(5):587-592
Two members of a new family of inorganic phosphates of general formula AIBII6(P2O7)2P3O10; KMn6(P2O7)2P3O10 (a=5.405(2), b=26.918(11), c=6.660(5), β=107.31(3)°, V=925.1(9) Å3, space group P21/m, Z=2, Dcalc=3.481 Mg m−3, R=0.0377 for 2235 observed reflections) and AgMn6(P2O7)2P3O10 (a=5.424(7), b=26.97(4), c=6.627(9), β=106.81(7)°, V=928(2) Å3, space group P21/m, Z=2, Dcalc=3.716 Mg m−3, R=0.0594 for 1577 observed reflections) have been synthesized and identified by single crystal X-ray diffraction. The isostructural complexes present an interesting comparison of silver and potassium bonding.  相似文献   

20.
1 INTRODUCTION The design and synthesis of polynuclear com- plexes have attracted chemists?attention in the contemporary chemistry, since their clusters maybe lead to novel materials with magnetic, optical, electronic and catalytic properties of the constituent metals[1~3]. It is also prevalently interesting to synthesize high-nuclearity metal complexes for their nanoscopic dimensions[3, 4]. Spectroscopic properties of the lanthanides are widely used in the study of biological systems. …  相似文献   

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