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1.
A 3D infinitely extended structural rare earth coordination compound with a formula of K3{[Sm(H2O)7]2Na[α-SiW11O39Sm(H2O)4]2}·14H2O has been synthesized by reaction of Sm2O3, HClO4, NaOH with α-K8SiW11O39·nH2O, and characterized by IR, UV spectra, ICP, TG-DTA, cyclic voltammetry, variable-temperature magnetic susceptibility and X-ray single-crystal diffraction. X-ray single-crystal diffraction indicates that the title compound crystallizes in a triclinic lattice, Pī space group, with a = 1.2462(3) nm, b = 1.2652(3) nm, c = 1.8420(4) nm, α = 87.45(3)°, β = 79.91(3)°, γ= 82.57(3)°, Z = 1, R1 = 0.0778, wR2 = 0.1610. Structural analysis reveals that Sm3+(1) coordination cation has incorporated into the vacant site of [α-SiW11O39]8− entity, forming the [α- SiW11O39Sm(H2O)4]5− subunit. The two adjacent [α-SiW11O39Sm(H2O)4]5− subunits are combined with each other through two Sm(1)-O-W bridges accompanying the formation of dimmer structural unit [α-SiW11O39Sm(H2O)4]2 10− of the title compound. The neighboring dimmer structural units [α-SiW11O39Sm(H2O)4]2 10− are linked to form the 1D chainlike structure by means of two Sm3+(2) and a Na+(1) coordination cations. The K+(1) cations connect the 1D packing chains constructing the 2D netlike structure, and adjacent netlike layers are also grafted by K+(2) cations to build the novel 3D infinitely extended structure. The result of TG-DTA curves manifests that the decomposition temperature of the title polyanionic framework is 554°C. The cyclic voltammetry measurements show that the title polyanion has the two-step redox processes in aqueous solution with pH = 3.1. Variable temperature magnetic susceptibility indicates the title compound obeys the Cruie-Weiss Law in the higher temperature range from 110 to 300 K, while in the lower temperature range from 2 to 110 K the comparatively strong antiferromagnetism interactions can be observed.  相似文献   

2.

Abstract  

Heat capacities of PbCrO4(s), Pb2CrO5(s), and Pb5CrO8(s) were measured by differential scanning calorimetry. The measured heat capacities as a function of temperature are expressed as C p <PbCrO4> J K−1 mol−1 = 150.37 + 27.74 × 10−3 T − 2.80 × 106 T −2 (T = 300–750 K), C p <Pb2CrO5> J K−1 mol−1 = 194.55 + 76.09 × 10−3 T − 4.64 × 106 T −2 (T = 300–700 K), and C p  <Pb5CrO8> J K−1 mol−1 = 323.35 + 184.80 × 10−3 T − 5.48 × 106 T −2 (T = 300–600 K). From the measured heat capacity data, thermodynamic functions such as enthalpy increments, entropies, and Gibbs energy functions were derived.  相似文献   

3.
The dimeric Fe(III)-substituted α-Keggin tungstogermanate {[α-GeFe2W10O38(OH)]2}14− (1) was synthesized by reaction of iron(III) with [A-α-GeW9O34]10− in neutral medium and characterized by elemental analysis, IR, UV-Vis, TG-DSC and electrochemistry. An X-ray single-crystal analysis was carried out on K14[α-GeFe2W10O38(OH)]2 ·34H2O, which crystallizes in the monoclinic system, space group P21/c, with a = 20.510(3) ?, b = 15.565 (2) ?, c = 17.998(2) ?, β = 114.672(2)° and Z = 2. The polyanion 1 consists of two [α-GeFe2W10O38(OH)] Keggin moieties linked via two bridging hydroxo groups, leading to a planar Fe4O2(OH)2 cluster. The two half-units are related by an insertion center. The locating of the hydroxo groups is done by the bond valence sum calculations. The TG-DSC results show that the polyanion 1 is stable below 520 °C.  相似文献   

4.
Single crystals of (CN3H6)2[(UO2)2(C2O4)(SeO3)2] were synthesized and studied by IR spectroscopy and X-ray diffraction. The compound crystallizes in the triclinic system with the unit cell parameters a = 7.1169(12) ?, b = 7.4874(10) ?, c = 8.9748(14) ?, α = 88.243(6)°, β = 74.546(6)°, γ = 81.445(6)°, space group P[`1]P\bar 1, Z = 1, R = 0.0304. The main structural units of the crystals are layers of the [(UO2)2(C2O4)(SeO3)2]2− composition; the layers belong to the crystal chemical group A 2 K 02 T 23 (A = UO22+ K 02 = C2O42−, T 3 = SeO3) of uranyl complexes. Uranium-containing complex groups are linked by electrostatic interactions and a network of hydrogen bonds with CN3H6+ guanidinium ions to form a three-dimensional framework.  相似文献   

5.
A complex of the composition KNa3[Fe3O(CH3COO)6(H2O)3]3 [α-P2W17Fe(H2O)O61]·32.5H2O (I) was obtained by interaction of FeCl3·6H2O and phosphotungstate K102-P2W17O61]·20H2O in an acetate buffer with a yield of 52%. Compound I was characterized by single crystal X-ray phase analysis and IR spectroscopy. In the crystal structure, the Na and K cations bind [Fe3O(CH3COO)6(H2O)3]+ trinuclear cations and [α-P2W17Fe(H2O)O61]7− heteropolytungstate anions into infinite zigzag chains. Original Russian Text Copyright ? 2005 by N. V. Izarova, M. N. Sokolov, A. V. Virovets, H. G. Platas, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 1, pp. 149–155, January–February, 2005.  相似文献   

6.
The homometal cluster [Fe(DMF)6][W22-S)2S4] (I) was successfully synthesized by low-temperature solid-state reactions. X-ray single-crystal diffraction studies suggest that compound I is a dinuclear anion cluster. The compound was characterized by elemental analyses, IR spectra, and UV-Vis spectra. The third-order nonlinear optical (NLO) properties of the cluster were also investigated and exhibited nice nonlinear saturation absorption (α2 < 0) that is rarer than reverse saturation absorption (α2 > 0) and self-defocusing property (n 2 < 0) and self-defocusing performance with modulus of the hyperpolarizabilities (9.547 × 10−31 esu) for I. The article was submitted by the authors in English.  相似文献   

7.
A solvothermal reaction of 2-pyrazinic acid with Zn(SO4)2 · 7H2O yielded the title complex of the formula {[Zn2(Pyz)2(H2O)4] · SO4} n (I). X-ray diffraction study shows that the complex I crystallizes in mono-clinic system, space group P21/c, with lattice parameters a = 11.2687(6), b = 7.3511(4), c = 11.8506(7) ?, β = 95.070(2)°, V = 977.83(9) ?3, Z = 4, and ρcalcd = 2.184 mg m−3.  相似文献   

8.
A novel dimeric polyoxotungstate K4LaH[As2W20CuO67(H2O)3 ]Cl2·22.5H2O has been synthesized and characterized by IR, element analysis TG and cyclic voltammogram. The anion K4LaH[As2W20CuO67(H2O) 3]Cl2·22.5H2O can be characterized as two {AsIIIW9O33}9− moieties linked via a {Cu(OH)}, a {W(H2O)} and a {WO(H2O)} group which total coordination numbers are respectively 5, 5, 6. An additional lanthanide atom connects the dimeric cluster via a W-O-La bond. The X-ray single crystal diffraction shows that it is in the triclinic system, space group P-1, with a = 12.287(6) ?, b = 20.197(1) ?,c=21.483(1)?,α = 62.584(8)°,β = 74.659(8)°,γ = 75.273(9)°,V = 4509(4)?3, Z = 2. To our known, the polyoxotungstate is the novel sandwich-type polyoxoanion, which is decorated by transition-metal and lanthanide atoms at the same time.  相似文献   

9.
A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF and characterized by IR, UV spectra and TG-DTA. The result of the X-ray single crystal diffraction indicates that the crystal is monoclinic, space group P21/n, with unit cell dimensional: a = 1.1983(3), b = 2.4216(5), c = 1.9517(4) nm, β = 92.91(3)°, Z = 4, R 1 = 0.07710, wR 2 = 0.1416. Structural analysis indicates that every [Ce(DMF)4(H2O)]3+ building block is surrounded by three adjacent [α-BW12O40]5− polyanions, meanwhile, every [α-BW12O40]5− polyanion interconnects with three neighboring [Ce(DMF)4(H2O)]3+ subunits, by making use of which two-dimensional network structure can be constructed. The result of thermogravimetric analysis manifests that the title compound has two-stage weight loss and the decomposition temperature of the title polyanionic framework is 560°C. The electrochemical analysis shows the title polyanion has three-step redox processes in the pH = 4–7 media.  相似文献   

10.
Heterometallic chloride complexes [Mo5NbI8Cl6] n (n = 2, 3) are synthesized. The crystal structures of their salts are determined: for (Ph4P)2[Mo5NbI8Cl6] (I), triclinic crystal system, spacegroup P [`1]\bar 1, a = 10.9886(6), b = 11.4604(5), c = 13.4343(7) ?, α = 66.124(2), β = 86.892(2), γ = 86.490(2)°, Z = 1, V = 1543.35(13) ?3; and for (4-MePyH)5[Mo5NbI8Cl6]Cl2 (II), monoclinic crystal system, space group C2/m, a = 16.4937(4), b = 14.7335(3), c = 11.6534(3) ?, β = 99.8750(10)°, Z = 2, V = 2789.94(11) ? The geometric parameters of compounds I and II and the conditions for the formation of the complexes with the charges −2 and −3 are discussed.  相似文献   

11.
Spheniscidite, a synthetic iron phosphate mineral has been synthesized by hydrothermal methods. The material is isotypic with another iron phosphate mineral, leucophosphite. Spheniscidite crystallizes in the monoclinic spacegroupP21/n. (a=9·845(1),b=9·771(3),c=9·897(1),β=102·9°,V=928·5(1),Z=4,M=372·2,d calc=2·02 g cm−3 andR=0·02). The structure consists of a network of FeO6 octahedra vertex-linked with PO4 tetrahedra forming 8-membered one-dimensional channels in which the NH4 + ions and H2O molecules are located. The material exhibits reversible dehydration and good adsorption behaviour. Magnetic susceptibility measurements indicate that the solid orders antiferromagnetically.  相似文献   

12.
Abstrtact  An organic-inorganic polymer of [Pr(DMF)6Pr(DMF)7(P2W18O62)] n has been synthesized in acetonitrile-water (5 : 2, volume ratio) mixed solvent. Single-crystal X-ray structural analysis indicates that the title compound crystallizes in a monoclinic lattice, P21/C, with a = 1.8574(4), b=2.3907(5), c=2.4222(5) nm, β=99.48(3)°, Z = 4, ∨=10.609(4) nm3, D c =3.501 Mg/m3, F(000)=9972, R1=0.0654 and wR 2= 0.1098. The result of crystal structure analysis reveals that Pr3+(1) complex ion is eight-coordinated with a distorted bicapped trigonal prismatic environment, which is combined with the heteropolyanion by terminal oxygen atom, whereas Pr3+(2) complex ion is also eight-coordinated with a distorted square antiprismatic environment, which is linked to the heteropolyanion by terminal oxygen atom. Adjacent structure units of [Pr(DMF)6Pr(DMF)7(P2W18O62)] are bridged through W-O-Pr1-O-W links to form an unprecedented one-dimensional zigzag linear chain by alternate polyanions and cationic units in the polymer. Thermal analysis reveals that the framework of the title polyanion decomposes at 613.8°C.  相似文献   

13.
Two new octahedral Cd(II) complexes [Cd(L)2] (1) and {[Cd(LH)2(SCN)2]H2O} (2) [where LH = C14H13N3O] are synthesized using a tridentate hydrazone ligand (LH) and they are characterized by elemental analysis, IR spectra, NMR spectra, thermal studies and finally the structures have been determined by single crystal X-ray diffraction. Complex 1 crystallizes in monoclinic system, space group C2/c with a = 22.565(6) ?, b = 10.252(3) ?, c = 12.187(4) ?, β = 118.851(2), and Z = 4. Complex 2 also crystallizes in the monoclinic system, space group P21/c with a = 9.257(9)?, b = 17.809(2)?, c = 9.548(9)?, β = 107.439(4), and Z = 2. In 1 the ligand binds the Cd(II) ion in tridentate fashion, whereas in 2 it acts as a bidentate ligand.  相似文献   

14.
A new layered tin(II) phosphate [Sn2(PO4)2]2−[C2N2H10]2+·H2O was synthesized by hydrothermal technique. It crystallizes in monoclinic space groupP21/c(No. 14) with lattice parametersa=9.4112(1) Å;b=8.5998(1) Å;c=15.9921(2) Å;β=100.009(1)°;V=1274.61(2);Z=4;R=2.06%;Rw=2.17%. The structure consists of inorganic layers, comprising a network of strictly alternating SnO3and PO4moieties and held together by strong hydrogen bonding between the layers. Protonated ethylenediamine and water molecules are trapped between the layers.  相似文献   

15.
The thallium-barium double nitrite, TlBa2(NO2)5, is pyroelectric in the 77-600 K range and crystallizes in thePca2 1 space group. The lattice constants at 293 K are: a = 17.868(12),b = 4.934(3),c = 13-426(11) A (MoKa, λ = 0.71069 A). There are four stoichiometric units in the unit cell of volume V= 1184(1) A3 (D o = 3.98,D x = 3.979 Mgm−3),F (000) = 1232, μ = 20.36mm−1. The crystal structure was solved by Patterson and Fourier methods and refined by least-squares to a final conventional agreement indexR = 0.053 for 1371 independent reflections collected in a θ range of 3–30°, using MoKα radiation. There are two independent barium atoms surrounded by NO 2 groups, both with coordination number 10 and distances in the ranges Ba-O = 2.69(4)-3.18(4) A and Ba-N = 3.01(4)-3.18(4) A. The environment of thallium is clearly affected by the lone-pair stereoactivity and involves 12 Tl-O and Tl-N contacts less than 3.5A, but only four Tl-O distances are shorter than 3 A (min. 2.76(2), max. 2.85(3) A), with a pyramidal coordination and thallium at the apex of the pyramid. All these coordination polyhedra are joined in chains running along the shortest lattice vector [010]. The single crystal electronic spectra, studied in absorption with polarized light and in photostimulated emission, are interpreted as due to transitions involving NO 2 electronic levels perturbed by Tl+, whose spin-orbit interaction makes probable also the forbidden singlet-triplet transitions, in agreement with the interpretative picture given for post-transition metal nitrites.  相似文献   

16.
The cluster compounds, [MoAu2S4(PPh2Py)2] ( 1 ) and [WAu2S4(PPh2Py)2] ( 2 ), were synthesized by the reaction of (NH4)2MS4 (M = Mo, W), H[AuCl4]·4H2O and diphenyl‐2‐pyridyl‐phosphine (PPh2Py) in CH2Cl2 solution. [MoAu2S4(PPh2Py)2] crystallizes in the monoclinic space group P21/c with a = 18.385(2), b =12.304(1), c = 16.904(2) Å, β =110.722(2)°, and Z = 4. [WAu2S4(PPh2Py)2] crystallizes in the triclinic space group P‐1 with a = 9.333 (3), b = 10.628(3), c = 19.566(6) Å, α = 89.26(1), β = 80.87(1), γ = 68.85(1)°, and Z = 2. Single crystal X‐ray analysis showed that these two compounds are isostructural, but belong to different space groups. The Mo (W) atom has a slightly distorted tetrahedral coordination, and the two Au atoms are distorted from trigonal planar, the P—Au—M—Au—P chain is nearly linear. Measurement of the nonlinear optical (NLO) properties using the Z‐scan technique with an 8‐ns pulsed laser at 532 nm showed that 1 and 2 possess NLO absorption and effective self‐focusing effect. The effective α2 and n2 values of cluster 1 are 5.89 × 10—12 m · W—1 and 6.45 × 10—18 m2 · W—1; the effective α2 and n2 values of compound 2 are 4.35 × 10—11 m · W—1 and 3.73 × 10—17 m2 · W—1.  相似文献   

17.
Single crystals of diammonium tetranitratouranylate (NH4)2[UO2(NO3)4] (I) and a new diammonium tetranitratouranylate complex with 18-crown-6 [(NH4)(18C6)]2[UO2(NO3)4] (II) have been synthesized by the reaction of diaquadinitratouranyl tetrahydrate with ammonium nitrate in a nitric acid solution and the reaction of the same reagents with 18C6 in an ethanol solution, respectively. The X-ray diffraction analysis of compounds I and II has been performed. Crystals of compounds I and II are monoclinic, Z = 2, space group P21/n, a = 6.4075(5) ?, b = 7.7851(7) ?, c = 12.4461(12) ?, β = 101.239(1)°, V = 608. 94(9) ?3 for compound I and a = 10.542(9) ?, b = 8.590(8) ?, c = 22.5019(19) ?, β = 101.632(1)°, V = 2058.3(3) ?3 for compound II. The [UO2(NO3)4]2− complex anion in compounds I and II contains two monodentate and two bidentate cyclic nitrato groups, and the coordination number of uranyl is 6. The 18C6 molecule in the structure of compound II has the classic crown conformation and combined with the ammonium ion by three hydrogen bonds. Compounds I and II formed by electrostatic attraction forces between counterions are stabilized by (NH4+)NH...O(NO3) interionic hydrogen bonds.  相似文献   

18.
Solid-state reduction of WCl6 with Hg followed by incomplete sublimation of mercury chlorides generated the tritungsten decachloride—mercury chloride adducts W3Cl10(Hg2Cl2)2−x(HgCl2)x. Thermal equilibration of the solid-state products followed by sublimation of HgCl2 afforded single crystals that include the mercurous chloride adduct W3Cl10(Hg2Cl2)2. Single-crystal diffractometry revealed a one-dimensional polymer of tritungsten decachloride triangular clusters with novel terminal and inter-cluster-bridging ClHgHgCl ligands. The W3 cluster core has similar metrics to that of the benzyltriethylammonium salt of W33-Cl)(μ-Cl)3Cl9 3−. W3Cl10(Hg2Cl2)2 is the first reported adduct of the binary tungsten chloride W3Cl10. The ClHgHgCl ligands are more labile that the terminal chlorine atoms of W33-Cl)(μ-Cl)3Cl9 3−. These results demonstrate diverse roles and potential utility of main group element halide by-product ligands in solid-state reductions of transition metal halides.  相似文献   

19.
The complex [Ag(DDM)2(CH3C6H4NH2)]NO3, where DDM is 4,4-diaminodiphenylmethane [CH2(C6H4NH2)2], was synthesized and its structure was determined. The crystals are monoclinic, space group P21/n, a = 9.543(2) ?, b = 18.056(4) ?, c = 1.901(2) ?, β = 106.94(3)°, V = 1796.8(6) ?3, ρcalcd = 1.443 g/cm3, Z = 4. The Ag atom (at the inversion center) is coordinated at the vertices of an almost undistorted octahedron by six nitrogen atoms of the primary amino groups from four bridging DDM molecules and two terminal p-toluidine molecules (Ag-N, 2.546(3) ?; NAgN, 89.7–90.3°). Wavelike layers composed of conjugate multiunit metal rings, each containing four Ag+ ions and four bridging DDM ligands, are formed in the structure in the [101] direction (a 2D polymer). Uncoordinated NO 3 anions are arranged in the cavities between the layers and link them by N-H⋯O hydrogen bonds. Original Russian Text ? Yu.V. Kokunov, V.V. Kovalev, Yu.E. Gorbunova, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 12, pp. 1992–1998.  相似文献   

20.
A new compound [MNII(Phen)3]2+(B6H7)2 is synthesized; its crystal structure is studied by XRD at 100 K. Crystallographic data: C36H38B12N6Mn, M = 739.39, triclinic symmetry, space group P , unit cell parameters: a = 10.3131(3) ?, b = 13.4839(4) ?, c = 15.1132(4) ?; α = 97.696(1)°, β = 108.324(1)°, γ = 102.211(1)°; V = 1903.9(1) ?3, Z = 2, d calc = 1.290 g/cm3. The structure is solved by direct and Fourier methods and refined by full-matrix LSM in the anisotropic (isotropic for hydrogen atoms) approximation to the final factor R 1 = 0.036 for 10169 I hkl ≥ 2σ I (Bruker-Nonius X8 APEX CCD diffractometer, λMoK α). The structure contains two crystallographically different anions. Original Russian Text Copyright ? 2009 by T. M. Polyanskaya, M. K. Drozdova, V. V. Volkov, and K. G. Myakishev __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 381–385, March–April, 2009.  相似文献   

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