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1.
Crystal Structure and Phase Transitions of As(CH3)4I The crystal structure of α-As(CH3)4I at room temperature was determined using single crystal data: cubic, space group Pa3 , a = 1 198.0(2) pm. Therefore α-As(CH3)4I displays a novel crystal structure, which is not comparable to known AB-Typ structures with respect to the arrangement of anions and the baricenters of the complex cations. Differential thermal analysis showed three phase transitions at 103, 175 and 215°C. The lattice parameters of the high temperature phases (temperature dependent Guinier measurements) are: β-As(CH3)4I (tetragonal): a = 845.2(2) pm, c = 615.0(2) pm; γ-As(CH3)4I (hexagonal): a = 737.7(2) pm, c = 1 082.2(3) pm; and to δ-As(CH3)4I (hexagonal): a = 705.8(2) pm, c = 1 147(1) pm. β-and γ-As[(CH3)]4I are isotypic to N(CH3)4Cl and As(CH3)4Br, respectively.  相似文献   

2.
Thermal Behaviour and Crystal Structure of YAl3Cl12 We determined the thermodynamic data of YAl3Cl12 ΔH = ?739.9 ± 3 kcal/mol and S = 136.1 ± 4 cal/K · mol by total pressure measurements and ΔH = ?739.1 ± 1.6 kcal/mol by solution calorimetry. Using DTA-investigations we established the phase diagram in the system AlCl3–YCl3. The crystal structure was refined on the basis of single crystal data (P31 12; Z = 3; a = 1 046.8(2); c = 1 562.3(3) pm).  相似文献   

3.
Mercury Compounds with Cyancarbanions. I . Synthesis and Crystal Structure of Dimercury(I)-bis(tricyanmethanide ) With the triclinic unit cell, space group P1 , with the lattice constants a = 5.2794(1) Å, b = 9.9279(1) Å, c = 11.3376(2) Å, α = 71.004(4)°, β = 76.459(2)° and γ = 74.601(4)° are two formula units. The three-dimensional network, which characterizes the structure, results from dimercury(I) ions with sp3 hybridization, which form beside the homonuclear metal bonding three covalent bonds to cyanonitrogen atoms. The tricyanmethanide ion acts by losing symmetry as a tridentate ligand.  相似文献   

4.
Synthesis and Crystal Structure of [Li(DME)2I] . LiI can be dissolved at 50°C in toluene/DME (2:1). At - 20°C [Li(DME)2I] ( 1 ) was isolated in 75% yield. 1 was characterized by NMR techniques as well as an X-Ray structure determination. 1 crystallizes in the space group C2/c with a = 1 356.9(2), b = 813.2(1), c = 1 259.1(2) pm, and β = 99.74(1)°.  相似文献   

5.
Synthesis, Crystal Structure and Magnetic Behaviour of Gd(CF3CF2COO)3(H2O)3 Single crystals of Gd(CF3CF2COO)3(H2O)3 have been obtained by reaction of Gd2O3 with an aqueous solution of CF3CF2COOH. The compound crystallizes triclinically in the space group (No. 2; Z = 2; a = 928.5(1) pm, b = 1037.1(1) pm, c = 1147.3(2) pm, α = 90.44(2)°, β = 108.56(1)°, γ = 106.49(1)°). In the crystal structure the gadolinium ions are bridged by carboxylate groups to dimers and are coordinated eightfold by oxygen atoms. The magnetic behaviour was investigated in the temperature range of 1.77 to 300 K. The magnetic data indicate weak antiferromagnetic interactions within the dimeric unit (Jex = ?0.0057 cm?1).  相似文献   

6.
Crystal Structure of CF3TeTeCF3. Synthesis, Characterization, and Properties of CF3TeI Te2(CF3)2 crystallizes in the monoclinic space group P21/a with four formular units in the unit cell. The lattice constants are a = 10.13(1) Å, b = 11.489(7) Å, c = 6.822(8) Å and β = 101.20(8)°. CF3TeI is prepared by a quantitative reaction of Te2(CF3)2 with equimolar amounts of iodine. This compound is very instable, no isolation is possible. NMR spectra have been registrated. From metathesis reactions CF3TeX (X = C?CC6H5, t-C4H9, SCN, SC6F5) are prepared.  相似文献   

7.
Synthesis, Crystal Structure and Thermal Behaviour of Cs1,5[Re3I3Cl7,5(H2O)1,5] Dark brown tetrahedra of Cs1,5[Re3I3Cl7,5(H2O)1,5] crystallize on slow cooling of a hot saturated solution of ReI3 and CsCl in conc. hydrochlorid acid. The crystal structure (cubic, P4 3m (No. 215), a = 1241.06(3)pm, Vm = 287.8(1) cm3mol?1, Z = 4, R = 0.067, Rw = 0.037) is built up from isolated building units [Re3I3Cl7,5(H2O)1,5]1,5? with statistical distribution of chloride ions and water molecules in the in plane, terminal positions. Consistent with the result based on the X-ray analysis, the IR-spectrum shows one band for the OH stretching frequencies of the water molecules coordinated to the Re3 triangle at 3240 cm?1. The anions are arranged in the fashion of a cubic closest packing with the cesium ions occupying all octahedral and one quarter of the tetrahedral interstices. Temperature-dependent Guinier-Simon photographs in connection with DTA/TG investigations reveal that Cs1,5[Re3I3Cl7,5(H2O)1,5] releases water at 190°C accompanied with a structural transition and the dehydration product decomposes at 370°C to Cs2ReCl6?xIx, Re3I3+yCl6?y and rhenium metal.  相似文献   

8.
Fluorinate with Trifluoromethylhypochlorite CF3OCl. Preparation and Crystal Structure Determination of Trifluoromethyliodine Tetrafluoride CF3IF4 The preparation of Trifluoromethyliodine tetrafluoride (CF3IF4), from Trifluoromethyliodide (CF3I) with Trifluoromethylhypochlorite (CF3OCl), and the crystal structure of CF3IF4 at 172(1) K is described. CF3IF4 crystallizes in the monoclinic space group P21/c with a = 762.2(7) pm, b = 842.9(10) pm, c = 856.4(7) pm, β = 99.65(7)° with four formula units per unit cell.  相似文献   

9.
10.
Chlorofluorinate with Trifluoromethylhypochlorite CF3OCl. Preparation and Spectroscopic Characterization of Trifluormethyliodinechloridefluoride CF3I(Cl)F The preparation of a new iodine(III) compound, trifluormethyliodinechloridefluoride CF3I(Cl)F, via oxidative addition of trifluoromethylhypochlorite CF3OCl to trifluoromethyliodide CF3I is described. The thermolabile compound has been characterized by i.r., Raman, 19F NMR, and mass spectroscopy.  相似文献   

11.
Preparation, Spectroscopic Characterization, and Crystal Structure of (CF3)2C(F)OH2+Sb2F11 Hexafluoroacetone, (CF3)2CO, reacts at –78 °C with the superacid HF/SbF5 under formation of the primary oxonium salt, (CF3)2C(F)OH2+Sb2F11, which is characterized by vibrational spectroscopy and NMR spectra. The salt crystallizes in the triclinic space group P1 with a = 817.9(1), b = 989.0(1), c = 1003.8(1) pm and 2 formula units per unit cell.  相似文献   

12.
Preparation and Crystal Structure of (CH3NH3)8[NdCl6][NdCl4(H20)2]2Cl3 (CH3NH3)8[NdCl6][NdCl4 (H2O)2]2Cl3 is for the first time prepared and investigated by X-ray, single crystal work. It crystallizes in the monoclinic system (space group C2/m, Z = 2) with a = 9.358(5), b = 17.424(9), c = 15.360(8) Å, β = 108.30(4)°. The structure contains besides isolated Cl? ions distorted [NdCl6]3? octahedra and [NdCl4(H2O)2]? chains.  相似文献   

13.
Spectroscopic Characterization and Crystal Structure of Trifluoromethyl Iodine(III) Chloride Trifluororacetate (CF3I(Cl)OCOCF3) The ternary iodine(III) compound CF3I(Cl)OCOCF3 is obtained by reaction between CF3I(Cl)F and (CH3)3SiOCOCF3 at –50 °C. The molecule was characterized by vibrational spectra, NMR‐spectra, and a crystal structure analysis. CF3I(Cl)OCOCF3 crystallizes monoclinic in the space group P21/c with a = 1102.7(1) pm, b = 785.6(1) pm, c = 989.7(1) pm, and β = 101.34(1)°.  相似文献   

14.
Synthesis and Crystal Structure of Na2Zn(OH)4 Crystallization from saturated sodium hydroxozincate solutions yields colourless platelets of crystals of Na2Zn(OH)4. The X‐ray structure determination on these crystals was successful including all hydrogen positions. P21/n, Z = 4, a = 7.959(3) Å, b = 6.534(1) Å, c = 8.501(3) Å, β = 93.97(3)°, N(F2o ° 2σ F2o) = 1668, N(Var.) = 81, R1/wR2 = 0.043/0.107. Na2Zn(OH)4 crystallizes in a layered structure. Alternate layers contain Na+ in octahedral and Zn2+ in tetrahedral coordination by OH.  相似文献   

15.
Mercury Compounds with Cyancarbanions. II Synthesis and Crystal Structure of Dimercury(I)-bis(1,1,3,3-tetracyanpropenide) The structure of dimercury(I)-bis(1,1,3,3-tetracyanpropenide), Hg2(tcp)2, has been determined by single-crystal X-ray diffraction methods. The crystals are monoclinic, space group P 21/n. The unit cell dimensions are: a = 9.9193(3) Å, b = 5.6912(6) Å, c = 13.3806(4), β = 92.544(4)° and Z = 2. The mercury atoms in the centrosymmetric cation are three-coordinate with Hg? Hg 2.503, Hg? N 2.207, 2.207, 2.560 Å. tcp behaves as a bidentate ligand forming infinite chains running parallel to the a-axis.  相似文献   

16.
Synthesis of Phenylnitrene Complexes with N-Trimethylsilylaniline. II. Characterization and Crystal Structure of the Rhenium(V) Complexes mer-[Re(NPh)Cl3(NH2Ph)(Ph3P)] and trans-[Re(NPh)(OMe)Cl2(Ph3P)2] Reaction of [ReOCl3(Ph3P)2] with N-trimethylsilylaniline yields mer-[Re(NPh)Cl3(Ph3P)2], which reacts under air with excess of N-trimethylsilylaniline to form [Re(NPh)Cl3 · (NH2Ph)(Ph3P)]. Crystallization from CH2Cl2/MeOH affords [Re(NPh)(OMe)Cl2(Ph3P)2] as an additional product. [Re(NPh)Cl3(NH2Ph)(Ph3P)] crystallizes in the monoclinic space group P21/n with a = 1 192.3(3); b = 1 918.9(3); c = 1 266.3(3) pm; β = 101.71(1)°; Z = 4. The rhenium atom has a distorted octahedral environment with the Cl atoms in meridional positions. The phenyl nitrene ligand is coordinated with an almost linear arrangement Re? N1? C40 = 166.8(6)° and with a bond distance Re?N = 170.5(6) pm. [Re(NPh)(OMe)Cl2(Ph3P)2] · 1/2CH2Cl2 crystallizes in the triclinic space group P1 : a = 1 103.1(4); b = 1 227.9(4); c = 1 711.3(5) pm; α = 70.48(3)°; β = 72.71(3)°; γ = 80.03(3)°; Z = 2. The rhenium atom exhibits a distorted octahedral coordination with the Cl atoms and the phosphine ligands in trans positions. As a consequence of the competition of the nitrene ligand and the trans-coordinated methoxy group the Re?;N bond length is slightly lengthened to 173.2(7) pm, while the Re? O bond length of 193.4(6) pm is short. The bond angles Re? N? C70 and Re? O? C80 are 173.3(7)° and 139.1(7)°, respectively.  相似文献   

17.
On the Reaction of the Lanthanides with Chelate Ligands Synthesis and Crystal Structure of [(py2CH)3Gd] GdBr3 reacts with [(py2CH)Li] to the mononuclear complex [(py2CH)3Gd] 1 . The structure of 1 was characterized by X-ray single crystal structure analysis. Space group P21, Z = 2, a = 951.4(10) pm, b = 1369.4(10) pm, c = 1074.5(10) pm, β = 105.69(8)°. The Gd-Ion is surrounded by the six nitrogen atoms of the three chelate ligands and shows a distorted trigonal prismatic coordination. As a difference to the lithium salt of the ligand, the six-membered metalla-cycles in 1 are not planar, but show a boat conformation.  相似文献   

18.
Perfluorosalkyl Tellurium Compounds: Oxidation of (CF3)2Te; Preparations and Properties of (CF3)2TeCl2, (CF3)2TeBr2, (CF3)2Te(ONO2)2, and (CF3)2TeO From the oxidation of (CF3)2Te with Cl2, Br2, O2, and ClONO2 the new trifluoromethyl tellurium compounds (CF3)2TeCl2, (CF3)2TeBr2, (CF3)2TeO, and (CF3)2Te(ONO2)2 are prepared. The 19F, 13C and 125Te n.m.r. spectra, the vibrational and mass spectra as well as the chemical properties of these compounds are described. By variation of the reaction conditions CF3TeCl3 and CF3TeBr3 are also formed. It has not been possible to isolate (CF3)2TeI2, but there is some evidence that it is formed as an intermediate. (CF3)2Te reacts with ozone to a very unstable compound, which decomposes at low temperature.  相似文献   

19.
Synthesis and Crystal Structure of (PPh4)2Se6 (PPh4)2Se6 has been prepared by the reaction of selenium with K2Se2 in dimethylformamide solution in the presence of K3[Mn(CN)6] and PPh4Br, forming black crystal needles. According to the crystal structure determination the compound consists of PPh+4 ions and chainlike hexaselenide ions. Space group P6 , Z = 2,4683 Observed unique reflections, R = 0.066. Lattice dimensions at ?90°C: a = 951.0, b = 1094.8, c = 2137.4 pm, α = 82.66°, β = 83.36°, γ = 89.96°.  相似文献   

20.
Preparation and Crystal Structure of Rb2Ni3Se4 The compound Rb2Ni3Se4 was synthesized by heating a mixture of rubidium carbonate, nickel and selenium at 850°C in an atmosphere of hydrogen. The compound has a golden lustre and crystallizes with the K2Pd3S4-type structure; a = 10.555(3) Å, b = 27.588(6) Å, c = 6.031(6) Å, Z = 8, Fddd (No. 70). The structure can be described as a stacking of layers of the composition Rb2Ni3Se4 with a stacking sequence abcd. The electrostatic part of lattice energy (MAPLE) will be discussed for compounds of the compositions A2M3X4 (A K, Rb, Cs; M Ni, Pd, Pt and X S, Se).  相似文献   

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