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1.
Complexes [(4-MeC6H4)4Sb] 2 + [Hg2I6]2? (I), [(4-MeC6H4)4Sb] 2 + [HgI4]2? (II), [(4-MeC6H4)4Sb] 3 + [Sb3I12]2? (III), were synthesized by reactions of tetra-p-tolylantimony iodide with mercury iodide and antimony iodide, respectively. Tetra-p-tolylantimony perrhenate [(4-MeC6H4)4Sb]+[ReO4]? (IV) was prepared from tetra-p-tolylantimony chloride and sodium perrhenate in acetone. Crystal structures of complexes I, II, and IV were determined by X-ray crystallography. Mercury and rhenium atoms have tetrahedral coordinations in these complexes. The Hg-I and Re-O distances in the structures of I, II, and IV vary within 2.7719(13)–2.7908(12)Å, 2.7028(3)–2.9163(3) Å, and 1.693(3)–1.744(3) Å, respectively. Antimony atoms in two crystallographically independent trinuclear centrosymmetric [Sb3I12]2? anions of complex III have an octahedral environment. Each terminal SbI3 fragment (Sb-It, 2.8265(9)–2.8333(10)Å) is bound to the central atom through tree bridging iodine atoms (Sb(2)-Ibr, 3.2275(9)–3.3620(10)Å). The distances between the central Sb atom and bridging iodine atoms are much shorter (Sb(1)-Ibr, 3.0153(6)–3.0316(6) Å; Sb(3)-Ibr, 2.9926(6)–3.0074(6) Å).  相似文献   

2.
We have studied and characterized the structural and vibrational properties of 2R-(-)-6-hydroxytremetone, isolated from Xenophyllum poposum (Phil.) by infrared and Raman spectroscopy in the solid phase. The density functional theory (DFT) method together with Pople's basis set show that two stable molecules for the compound have been theoretically determined in the gas phase and that both conformations are present in the solid phase, as was experimentally observed. The harmonic vibrational wavenumbers for the optimized geometry were calculated at B3LYP/6-31G*and B3LYP/6-311++G** levels. For a complete assignment of the vibrational spectra, DFT calculations were combined with Pulay's Scaled Quantum Mechanics Force Field (SQMFF) methodology in order to fit the theoretical wavenumber values to the experimental ones. Then, a complete assignment of all the observed bands in the infrared spectrum for the compound was performed. The natural bond orbital (NBO) study reveals the characteristics of the electronic delocalization of the two structures, while the corresponding topological properties of electronic charge density are analyzed by employing Bader's Atoms in the Molecules theory (AIM).  相似文献   

3.
The reaction of MoO2(acac)2 and dibenzylphosphinic acid in ethanol leads to a red distorted cubic tetrameric cluster, Mo4(??3-O)4(??2-O2P(CH2C6H5)2)4O4, and a pink open mixed-valent cluster, Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6, when the reduction is carried out at 120 and 75 °C, respectively. 95Mo NMR spectroscopy revealed a singlet for Mo4(??3-O)4(??2-O2P(CH2C6H5)2)4O4 (1) at 584.9 ppm (????1/2 = 4500 Hz) and two resonances for Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6 (2) at 238.8 ppm (????1/2 = 1250 Hz) and 6.4 ppm (????1/2 = 5999 Hz), which were assigned to the Mo(V) and Mo(VI) sites, respectively. DFT geometries and 95Mo DFT-GIAO chemical shifts for Mo4(??3-O)4(??2-O2P(CH3)2)4O4 (3) and Mo4(??3-O)2(??2-O2P(CH3)2)6O6 (4) are consistent with X-ray crystallography and 95Mo NMR of 1 and 2. The open complex, Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6·2(CH2Cl2), exhibits a central Mo(V)?CMo(V) single bond at 2.6217(5) Å with each Mo(V) atom bonded to one oxo (trans-disposed) terminal ligand.  相似文献   

4.
X-ray diffraction study of tetranuclear organobismuth complexes Bi4(O)2(O2CC6H2F3-3,4,5)8 · 26-C6H6 and Bi4(O)2(O2CC6H2F3-3,4,5)8 · 2(C6H4Me2-1,4) revealed four Bi atoms connected through the bridging carboxylate ligands and the O atoms. The coordination sphere of the terminal Bi atoms includes the chelate carboxylate ligand and the 6-arene molecule. The bridging O atoms are tricoordinated, the distances between the terminal Bi atom and the center of benzene molecule (1,4-dimethylbenzene) are 3.024 Å(3.131 Å).Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 1, 2005, pp. 4–11.Original Russian Text Copyright © 2005 by Sharutin, Egorova, Sharutina, Ivanenko, Adonin, Starichenko, Pushilin, Gerasimenko.  相似文献   

5.
Two new title compounds have been prepared in powder form. Their spectral data are found to be consistent with the structure foundin Hofmann-Td-type clathrates.  相似文献   

6.
《Polyhedron》1999,18(21):2781-2785
The compounds (NH4)6[Mo6V2O24(C2O4)2]·6H2O (I) and (NH4)4[H2Mo2V2O12(C2O4)2]·2H2O (II) have been prepared from molybdenum(VI) oxide and ammonium vanadate in aqueous solution through the addition of ammonium oxalate, and their structures determined by X-ray structure analysis. Whereas the molybdovanadate anion [Mo6V2O24(C2O4)2]6− found in (I) consists of six MoO6 and two VO6 edge-sharing octahedra of the γ-[Mo8O26]4− type structure, the tetranuclear anion [H2Mo2V2O12(C2O4)2]4− of (II) adopts the structure with a M4O16 core. Both complexes contain bidentate oxalato ligands bonded to the vanadium ions. In both crystal structures the molybdovanadate anions are mutually hydrogen bonded by ammonium ions and water molecules.  相似文献   

7.
测定了Mo_4(μ_(3-)O)_2O_4Cl_2(O_2CC_6H_5)_6和Mo_4(μ_(3-)O)_2O_4Cl_2(O_2CC_6H_4CH_3)_6·2C_6H_5Cl四钼簇合物在N,N-二甲基甲酰胺溶液中的循环伏安特性、电子吸收光谱、固体粉末样品的表面光电压谱和光声光谱。讨论Mo_2(V)结构单元中弱M—M键的特性,认定了Mo—Mo键前线区域轨道的对称标号。  相似文献   

8.
Two Cu(II) hydroxo succinates [Cu3(H2O)2(OH)2(C4H4O4)2]?·?4H2O (1) and [Cu4(H2O)2(OH)4(C4H4O4)2]?·?5H2O (2) and one Cu(II) hydroxo glutarate [Cu5(OH)6(C5H6O4)2]?·?4H2O (3) have been prepared and structurally characterized by single crystal X-ray diffraction methods. They feature 1D and 2D copper oxygen connectivity of elongated {CuO6} octahedra in “4?+?1?+?1” and “4?+?2” coordination geometries. Within 1, linear trimers of three edge-sharing {CuO6} octahedra are connected into copper oxygen chains, which are bridged by the anti conformational succinate anions to generate 2D layers with mono terminally coordinating gauche succinate anions on both sides. The layers are assembled into a 3D framework by interlayer hydrogen bonds with lattice H2O molecules distributed in channels. Different from 1, the principal building units in 2 are linear tetramers of four edge-sharing {CuO6} octahedra. The tetramers are condensed into copper oxygen chains and the succinate anions interlink them into a 3D framework with triangular channels filled by lattice H2O molecules. The {CuO6} octahedra in 3 are edge-shared to form unprecedented 2D inorganic layers with mono terminally coordinating glutarate anions on both sides. Interlayer hydrogen bonding interactions are responsible for supramolecular assembly of the layers into a 3D framework with lattice H2O molecules in the channels. The inorganic layers in 3 can be described as hexagonal close packing of oxygen atoms with the Cu atoms in the octahedral cavities. The title compounds were further characterized by elemental analyses, IR spectra and thermal analyses.  相似文献   

9.
A novel Mn4 mixed salt, {[(n-Bu4N)(ClO4)2]2[Mn4O6(Tacn)4](ClO4)} · 2H2O (I) and its analogue [Mn4O6(Tacn)4](ClO4)4 · 2H2O (II) (Tacn = 1,4,7-triazacyclononane), have been constructed and structurally characterized by X-ray crystallography. The [Mn4O6]4+ core of these two complexes presents an adamantine-like skeleton. Each Mn atom of both complexes is coordinated by three nitrogen atoms of Tacn and connects other Mn atoms through a single-oxo bridge in an octahedral environment. Two complexes crystallize in monoclinic crystal system, space group C2/c with a = 24.296(11) Å, b = 10.986(5) Å, c = 32.746(15) Å, β = 101.975(6)°, Z = 8 for I and space group P21/n with a = 21.141(10), b = 11.306(5), c = 21.576(10) Å, β = 111.155(5)°, Z = 4 for II.  相似文献   

10.
The organoantimony peroxide (Ar2SbO)4(O2)2 (Ar = C6H3OMe-2, Br-5) was synthesized by the oxidation of Ar3Sb with hydrogen peroxide in the presence or acetoxime or acetophenone oxime in dioxane. The product crystallizes with various content of the solvent molecules in the crystal unit cell [1.5 (I) and 6 (II), respectively]. An X-ray diffraction analysis of the solvates was performed. Four antimony atoms in the peroxide are in the octahedral coordination, and are linked through bridging oxygen atoms and two peroxide groups. The distances Sb-C, Sb-Obridge, Sb-Operoxide, O-O and Sb...Sb are 2.117–2.122, 1.960–1.972, 2.193–2.235, 1.461, 1.465 and 3.223–3.237 Å in I, and 2.112, 2.119, 1.957, 1,966, 2.204, 2,246, 1,467, and 3.2439 Å in II.  相似文献   

11.
合成了两种稀土高氯酸盐与L 脯氨酸配合物的晶体.经热重、差热、化学分析及对比有关文献,知其组成是[Pr2(L Pro)6(H2O)4](ClO4)6和[Er2(L Pro)6(H2O)4](ClO4)6,质量分数为99.24%和98.20%.选用RE(NO3)3•6H2O(RE=Pr,Er)、L Pro、NaClO4•H2O和NaNO3作辅助物,使用具有恒温环境的反应热量计,以2 mol•L-1 HCl作溶剂,分别测定了[2RE(NO3)3•6H2O+6L Pro+6NaClO4•H2O]和{[RE2(L PrO)6(H2O)4](ClO4)6+6NaNO3}在298.15 K时的溶解热.设计一热化学循环求得化学反应的反应焓ΔrHm分别是:63.904 kJ•mol-1和91.017 kJ•mol-1,经计算得配合物[RE2(L Pro)6(H2O)4](ClO4)6(s)在298.15 K时的标准生成焓ΔfHm(298.15 K)分别是-6 594.78 kJ•mol-1和-6 532.87 kJ•mol-1.  相似文献   

12.
Abstract

The synthesis of novel bis(N-aryl-imino-phosphoranyl)methanes of the type CH2(PR2?N-Ar)2 has been accomplished by reaction of methylene-bisphosphines with arylazides. These compounds have been fully characterized by 1H, 31P and 13C NMR, IR spectroscopy, Field Desorption Mass Spectroscopy (? FDMS) and elemental analysis. Variable temperature NMR experiments and single crystal X-ray structure determinations of CH2(PPh2?N-C6H4-CH3-4)2 (la) and CH2(PMe2?N-C6H4-NO2-4)2 (1f) reveal that bis(N-aryl-imino-phosphorany1)methane occurs as tautomer 1. Crystals of la are orthorhombic, space group Pcab, with a = 26.602(2), b = 20.521(1), c = 11.8859(7) Å and V = 6488.5(7) Å3 (2 = 8, R = 0.045 and Rw = 0.066). The crystals of lf are monoclinic, space group C/2c, with a = 20.153(4), b = 5.952(1), c = 16.930(5) Å, β = 106.24(3)° and V = 1949.6(6) Å3 (Z = 4, molecular symmetry C2, Rw = 0.051 and R, = 0.079). Both molecules consist of 2 iminophosphoranyl units bridged by a methylene group. The P?N bond distances of 1.568(2) and 1.566(2) Å for la and 1.580(4) Å for lf represent normal values for iminophosphoranyl compounds. The N-C bond lengths of 1.386(2) and 1.390(2) A (la) or 1.372(5) A for If indicate that some electron delocalisation over the N-aryl moiety takes place. In la the electron delocalisation takes place separately in each iminophosphoranyl entity, while in lf electron delocalisation occurs only in the N-aryl-NO2 moiety.

Compound la is easily deprotonated using lithium-diisopropylamide or NaH and shows typical iminophosphoranyl chemistry, since with CO2 an aza-Wittig reaction has been found and with HX (X?CI, Br) protonation of both imide nitrogen atoms has been observed.  相似文献   

13.
Two new benzene clathrates of the form Cd(Pyrazine)M(CN)4C6H6, where M = Cd or Hg, have been prepared and their infrared and Raman spectra are reported.  相似文献   

14.
15.
本文合成了标题配合物,对其红外光谱进行了研究.测定了配合物的晶体结构,结果表明,晶体属三斜晶系,P1空间群,单胞参数:α=11.549(2)(?),b=14.122(3)(?),c=15.654(?),α=97.01(2)°,β=102.70(2)°,γ=105.43(2)°,V=2355.94(0.87)(?)~3,Z=2.晶体结构是采用Patterson法和差值Fourier合成解出.经全矩阵最小二乘法修正,最后偏差因子R=0.0337,R_w=0.0364.晶体中甘氨酸与Sm原子的结合方式有三种:第一种甘氨酸的羧基离子以螯合桥式与Sm原子配位;第二种甘氨酸以羧基桥式与同一单元的两个Sm原子配位;第三种甘氨酸以酸基桥式连结两个相邻单元中的相邻Sm原子而形成一维无限长链结构.此外,每个Sm原子还与两个水分子成键,其配位数为9.  相似文献   

16.
17.
The disilazane (Ph2SiNC6F5)2 crystallises from benzene solution with four molecules of solvent in the orthorhombic space group Pnna with a 18.182(6), b 21.480(8) and c 13.631(5) Å, Z = 4. The structure was solved by direct methods and refined by least-squares to R 0.069 for 937 observed reflections. The Si2N2 ring is planar with NSiN and SiNSi angles of 85.2 and 95.5° respectively; the mean SiN distance is 1.755 Å. The C6F5 groups are twisted by ca. 16° from the Si2N2 plane and the benzene molecules are arranged face-on above and below each of the C6F5 groups. There are, in addition, short intermolecular contacts between four fluorines of each C6F5 group and hydrogen atoms from both solvate benzene and the phenyl groups of a symmetry related silazane. Attempts to refine the related (Me2SiNC6F5)2 structure were not successful, probably due to disorder.  相似文献   

18.
The metallophilic attraction between closed shellor pseudo closed shell metal atoms with the configura-tion of d10,s2,d8has received considerable attentionrecently mainly because such metal-metal interactionsare closely associated with many important chemicaland physical properties such as catalysis,electronicconductivity and luminescence[1].The d8-d10-s2closed-shell metallophilic interactions and ligand functionali-ty have resulted in the formation and isolation ofmultinuclear aggregates with …  相似文献   

19.
A novel complex,[Mn(C_6H_(12)N_4)_2(H_2O)_4][Mn(H_2O)_6][SO_4]_2·6H_2O,was synthesized and hexagonal single crystals with centimeter-scale sizes were obtained by the method of solvent evaporation.It was characterized by elemental analysis,infrared spectrum,thermogravimetric analysis and X-ray single-crystal diffraction.The complex belongs to triclinic crystal system,space group P■ with a=9.3390(8),b=13.3520(13),c=16.3207(13)?,α=100.7160(3)°,β=90.1020(10)°,γ=109.9490(5)°,V=1874.9(3)?~3,Z=2,D_c=1.542 g/cm~3,M_r=870.64,μ=0.876 mm~(-1),T=293(2) K,F(000)=916 and S=0.990.The crystal structure determination displayed a distorted octahedral geometry around the manganese atom,which is bound to two nitrogen atoms from hexamethylenetetramine,acting as monodentate ligands,and to four aqua ligands.Variable-temperature magnetic measurements of the complex indicate the presence of weak antiferromagnetic interaction between manganese centers.  相似文献   

20.
邻甲基苯荒酸四乙基铵盐分别与硝酸银和氯化铜反应,经毗啶重结晶,得到四核银簇合物Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4(晶体Ⅰ)和二核铜化合物Cu_2(o-CH_3-C_6H_4CSS_2)_2(Py)_(晶体Ⅱ)。用X射线单晶衍射法测定了它们的晶体结构。晶体Ⅰ的空间群为P2/n。晶胞参数:a=14.757(4),b=12.231(3),c=15.183(4)A,β=91.14(2)°,V=2739.95A~3,Z=2。2590个衍射点参与修正,最终偏差因子R=0.087。晶体Ⅱ的空间群为C_1~1-P1。晶胞参数:a=9.307(7),b=9.546(7),c=10.119(8)A,α=95.06(9),β=109.74(10),γ=118.86(10)°,V=705.94A~3,Z=1。1198个衍射点参与修正,最终偏差因子R=0.086。 Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4分子中Ag_4呈蝴蝶状构型,其配位情况与四核银簇合物Ag_4(a-C_(10)H_7CS_2)_4(Py)_4相似。Cu_2(o-CH_3C_6H_4CSS_2)_2(Py)_2分子构型与Cu_2(a-C_(10)H_7CSS_2)_2(Py)_2十分相似。Cu—Cu键长为2.608A。而且邻甲基苯荒酸与Cu~(2+)反应包括一个氧化还原反应,也与a-萘荒酸与Cu~(2+)反应相似。可以认为邻甲基苯荒酸与a-萘荒酸有相似的空间效应和电子效应。  相似文献   

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