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1.
1 INTRODUCTIONAmethodofspacegrouprevisionbywhichthestructurefactorsofthelower symmetrystructurearegeneratedandthestructureisthensolvedfromthesimulatedintensitydatahasbeenrecentlyreported[1].Thismethodisnowappliedtotherevi sionofthespacegroupofthemetal cl…  相似文献   

2.
[(C2H5)4N]2{Fe4S4[S2CN(C2H5)2]4}的晶体和分子结构   总被引:1,自引:0,他引:1  
[(C2H5)4N]2{Fe4S4[S2CN(C2H5)2]4}单晶样品在Nicolet-R3四圆衍射仪上收集X射线衍射数据. 分析结果给出其晶胞参数: a=22.125(6), b=11.313(3),c=25.053A; β=118.05(2)°; V=5534.19A^3, Z=4, 空间群Cc. 衍射数据经过Lρ因子和经验吸收效应校正. 分子中铁原子的位置从三维Patterson图上得到. 接着经过若干轮Fourier和差Fourier电子云密度合成, 发现全部其余非氢原子的坐标.氢原子位置根据理论模型计算. 结构修正最后收敛至R=0.073, Rw=0.069. 标题化合物是由[(C2H5)4N]^+和{FeS4[S2CN(C2H5)2]}^2^-组成的离子型化合物. 结构的主要特点表现在阴离子上, 而在阴离子中含有类立方烷型簇核Fe4S4. 该簇核中每个铁原子与五个硫原子配位, 其配位多面体构型均为畸变的四方锥.  相似文献   

3.
γ-Irradiated [(CH3)4N]2ZnF4 and [(CH3)4N]2CdF4 single crystals were investigated by electron paramagnetic resonance (EPR) and vibrational spectroscopy of their unirradiated forms at ambient temperature. It has been found that both compounds indicate the existence of (CH3)3+ radicals. The g factors were found to be isotropic and the hyperfine constant for protons of the methyl groups was measured as 28.9 G for this radical in these substances. Each methyl group rotates around its C3ν-axis and also rotates around the C3ν-axis of the (CH3)3+ radical. In addition to these motions, the C3ν-axis of the (CH3)3+ radical seems to rotate around the z-axis. These results were compared with the earlier studies in (CH3)3+ radical and discussed. The vibrational spectra of these two compounds were discussed in relation to other compounds containing tetramethylammonium salts. The assignments of the observed bands were discussed.  相似文献   

4.
The supramolecular complex [Zn{NH(CH2)4O}{S2CN(C2H5)2}2]2 · CH2N(CH2)4O}2 (I) has been synthesized and studied by X-ray crystallography and thermal analysis. The noncentrosymmetric complex is composed of two structurally nonequivalent molecules of the adduct of bis(diethyldithiocarbamato)zinc with morpholine, which are linked with the outer-sphere N,N’-dimorpholinomethane molecule through two hydrogen bonds N-H?O. The major differences between the adduct molecules are related to the strength of Zn-N bonds, spatial orientation of the coordinated morpholine heterocyclic rings, and the proportion between the contributions of the trigonal bipyramidal (TBP) and tetragonal pyramidal (TP) components to the geometry of zinc polyhedra. Calculations show that the geometry of the zinc polyhedra is almost halfway between TBP and TP. The thermal destruction of supramolecular compound I is accompanied by desorption of the outer-sphere and coordinated organic molecules. At the final stage, defragmentation of the “dithiocarbamate part” of the complex leads to the formation of ZnS.  相似文献   

5.
The crystal structures of a new solvate of the ditopic receptor 1,3-calix[4]-bis-crown-6, Bis-C6, and of 1,3-calix[4]-bis-(benzo-crown-6), Bis-benzoC6, are reported. Bis-C6.3 CH3CN (1) crystallizes in the monoclinic space group P21/n, a = 14.388(3), b = 26.947(8), c = 14.707(4) Å, = 113.19(3)°, V = 5241(5) Å3, Z = 4. Refinement led to a final conventional R value of 0.092 for 2723 reflections. The structure of (1) differs from the previously reported structure of Bis-C6.4 CH3CN by the conformation of one crown either chain. Two acetonitrile molecules are in the close neighbourhood of the crown ether cavities. Bis-benzoC6.3 CH3CN (2) crystallizes in the monoclinic space group P21/c, a = 10.391(4), b = 17.264(11), c = 30.426(9) Å, = 94.62(3)°, V = 5440(7) Å3, Z = 4. Refinement led to a final conventional R value of 0.106 for 2965 reflections. Two acetonitrile molecules are located near the crown ether cavities, as in (1). One of the crown ether conformations is the same as in the binuclear caesium complex of Bis-benzoC6, supporting the hypothesis of a preorganization of this ligand towards the complexation of this ion; the second crown ether chain is partially disordered.  相似文献   

6.
The Platinum(II) diamine with N,N-dimethylethylenediamine (N,N-dimeEn) [Pt{(CH3)2N(CH2)2NH2}Cl2] (I) was synthesized. The reaction of the diamine with pyridine gave Pt(II) tetramine [Pt{(CH3)2N(CH2)2NH2}Py2]Cl2 (II), which was oxidized with chlorine to give Pt(IV) triamine Pt{[(CH3)2N(CH2)2}PyCl3]Cl · H2O (III). The reaction of III with chlorine (chloroamidation) yielded chloroimide [Pt{(CH3)2N(CH2)2NCl}PyCl3] (IV). The IR spectra of complexes I–IV and UV/Vis spectra of III and IV were studied. X-Ray diffraction analysis was performed for III (monoclinic crystals, space group P21/c, a = 7.7437(6), b = 8.1100(7), c = 28.52992(2) Å, β = 93.7280(10)°, Z = 4, R hkl = 0.0420) and IV (orthorhombic crystals, space group Pna21, a = 15.7825(12), b = 7.4447(6), c = 12.3099(6) Å, Z = 4, R hkl = 0.0539). During oxidation of Pt(II) tetramine with chlorine, the pyridine molecule is removed from the cis position relative to the (CH3)2N group (trans position relative to the NH2 group) of N,N-dimethylethylenediamine. The reaction of chloroimide complex IV with concentrated HCl (dechloroamidation) at 20°C afforded the initial complex III; that at 100°C, gave triamine III together with Pt(IV) diamine [Pt(N,N-dimeEn)Cl4] (V) (monoclinic crystals, space group P21/n, a = 7.1278(5), b = 11.5384(8), c = 12.7501(9) Å, β = 93.23(10)°, Z = 4, R hkl = 0.0239).  相似文献   

7.
刘云清  陈启元  尹周澜  吴道新 《合成化学》2005,13(2):178-179,182
以(NH4)2MoS4,Et4NBr,HSCH2CH2SH为原料合成了新的簇合物——[Et4N]2[Mo2S4(SCH2CH2S)2],其结构经X射线四圆衍射仪,IR。UV及元素分析确证。其晶体属单斜晶系。晶胞参数为:a=1.0304(8)nm,b=1.4158(8)sin。c=1.1417(1)nm,V=1.63801nm^3,z=4。晶体结构经块状矩阵最小二乘法修正后,最终偏离因子R=0.084。  相似文献   

8.
以(NH4)2MoS4,Et4NBr,HSCH2CH2SH为原料,合成出[Et4N]2[Mo2S4(SCH23CH2S)2]簇合物,用X射线衍射法测定了晶胞结构.其晶胞参数为a=1.0304(8)nm,b=1.4158(8)nm,c=1.1417(1)nm,V=1.63801nm3,Z=4,晶体属单斜晶系,晶体结构经块状矩阵最小二乘法修正后,最终偏离因子R=0.089.此外还进行了红外光谱,紫外可见光谱的测定.  相似文献   

9.
《Polyhedron》1999,18(26):3545-3552
Selected ‘3+1’ mixed ligand oxorhenium and oxotechnetium complexes containing the SNS/S donor atom set have been modified by introduction of a bifunctional amine anchor on the p-position of the thiophenolato monodentate ligand. A representative series of complexes containing several tridentate ligands was prepared both at macromolar (Re complexes) and nanomolar (99mTc complexes) amounts. Coupling of these complexes to activated carboxylate groups was performed according to the ‘preformed chelate approach’ using benzoyl chloride as a model molecule. Coupling yields were high both at nanomolar and millimolar metal concentration, as revealed by high-performance liquid chromatographic analysis of 99mTc and Re species adopting parallel radiometric and photometric detection modes. All Re compounds have been characterized by classical analytical methods. In addition, the structures of representative parent ReO[CH3SCH2CH2N(CH2CH2S)2][p-SC6H4NH2] and daughter ReO[CH3SCH2CH2N(CH2CH2S)2][p-SC6H4NHCOC6H5] complexes were solved by X-ray crystallography. Both compounds adopt a distorted trigonal bipyramidal geometry around rhenium, wherein the oxo group and the sulfur atoms of the SNS ligand occupy the equatorial plane and the nitrogen atom and the sulfur of the monothiol are located at the apical positions trans to each other.  相似文献   

10.
The title compound has been synthesized by the reaction of HgI2 and [(CH3)3- NCH2CH2N(CH3)3]I2 with pH = 7.5 at room temperature, and its crystal structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group P21/c with a = 8.3075(8), b =15.8084(19), c =15.390(2)(°A), β = 95.192(4)o, V = 2012.9(4)(°A)3, Z = 2, Dc = 2.824 g/cm3, F(000) = 1502, C14H39N4O2Hg2I8, Mr = 1711.87, μ(MoKα) = 13.768 mm-1, the final R = 0.0465 and wR = 0.1293 for 3046 observed reflections with I > 2(I). The title compound consists of cations ([C8H22N2]2+) and anion (HgI42-), which are combined by static attracting forces to form the so-called organic-inorganic hybrid material.  相似文献   

11.
Platinum(II) cyclo-hexamethylenedithiocarbamate (HmDtc) complex, [Pt{S2CN(CH2)6}2] (I), and its solvated form, Pt{S2CN(CH2)6}2] · CHCl3 (II), are synthesized and characterized by the 13C MAS NMR data. The HmDtc ligands in structure I are not equivalent, whereas the solvation of the complex is accompanied by the structural unification of the initially nonequivalent HmDtc ligands. In addition, the spectra are characterized by the 13C-195Pt spin-spin coupling. The noncentrosymmetric molecular structure of compound I determined by X-ray diffraction analysis includes two nonequivalent dithiocarbamate ligands coordinated by the metal in the S,S′-bidentate mode. The central atom forming the [PtS4] chromophore (intraorbital dsp 2-hybrid state of platinum) shifts from the plane of four sulfur atoms by 0.07 Å in the vertex of the flattened tetragonal pyramid. The seven-membered heterocycles ?N(CH2)6 of the HmDtc ligands are oppositely directed in space relative to the [S4] plane (trans orientation). The thermal behavior of compounds I and II are studied by simultaneous thermal analysis. In both cases, the final product of the multistage thermal destruction of the complexes is reduced metallic platinum.  相似文献   

12.
The highly insoluble organic-inorganic hybrid ionic compounds N,N??-methylenedipyridinium tetrachloroplatinate(II) [(C5H5N)2CH2] · [PtCl4] and N,N??-methylenedipyridinium hexachloroplatinate(IV) [(C5H5N)2CH2] · [PtCl6] were obtained by the treatment of N,N??-methylenedipyridinium dichloride monohydrate [(C5H5N)2CH2]Cl2 · H2O with K2[PtCl4] or (NH4)2[PtCl6], respectively, in an aqueous solution. Both complexes were isolated, purified, characterised by elemental analysis, and their molecular structures were confirmed by powder X-ray diffraction. The crystal structure of both compounds consists of separated discrete dications [(C5H5N)2CH2]2+ and anions [PtCl n ]2? (n = 4 or 6). As anticipated, the dications formed a butterfly shape consisting of two pyridine rings bound to the methylene group via their N atoms, while the Pt centre had a square planar geometry in [(C5H5N)2CH2] · [PtCl4] and an octahedral coordination in [(C5H5N)2CH2] · [PtCl6]. Interestingly, both crystal structures are stabilised by intermolecular C-H??Cl non-standard hydrogen bonds, ??-?? ring interactions between two pyridine rings of adjacent dications, and also by Cl-?? interactions.  相似文献   

13.
杂多化合物在催化、医药、材料及光化学等方面具有广泛的应用前景 [1~ 4 ] ,其中钼磷多金属氧酸盐具有优异的氧化催化性能 [5,6 ] .近年来合成的新奇结构的钼磷多金属氧酸盐中已测定结构的有含帽[7,8] 和非帽[9~ 12 ] 系列 .本文利用水热法合成了未见文献报道的结构新颖的夹心型磷钼多金属氧酸盐[( CH3CH2 ) 4N]4 H3O{Na[( HMo2 O5) 3( HPO4 ) ( H2 PO4 ) 3]2 }· ( H2 PO4 ) 2 · 1 0 H2 O,并测定了其晶体结构 .1 实验与晶体结构分析1 .1 仪器与试剂 元素 Na用美国原子吸收分光光度计测定 ;C,H和 N用 Perkin- Elmer 2 4 0…  相似文献   

14.

Two ion pair complexes, [Ru(bpy)3]2[Fe(CN)6]I [sdot] 7H3O (1) and [Ru(bpy)3][Fe(CN)5NO](CH3OH) [sdot] H2O (2) (bpy = 2,2-bipyridine) have been synthesized and structurally characterized. X-Ray crystallographic structures of 1 and 2 both show Fe(III) and Ru(II) in distorted octahedral environments. In both complexes, H-bonding interactions between an uncoordinated water molecule and the nitrogen atom of a cyano group exist.  相似文献   

15.
Compounds [Cu2(CH2FCOO)4· 2CH3CN](CH3CN) (I) and Ag3(CF3COO)3(CH3CN)2(II) were synthesized and studied by X-ray structural analysis. Crystals Iare monoclinic, space group C2/c, a= 27.854(6), b= 8.286(2), c= 19.428(4) Å, = 106.82(3)°, V= 4292(2) Å3, Z= 8, R 1= 0.0426; crystals IIare triclinic, space group , a= 8.676(2), b= 9.819(2), c= 11.961(2) Å, = 95.27(3), = 109.59(3)°, = 104.60(3)°, V= 911.4(3) Å3, Z= 2, R 1= 0.0252. Structure Iis composed of the structural units (lanterns) typical of copper(II) carboxylates. The presence of an additional acetonitrile molecule noncoordinated by the copper atoms makes it possible to consider compound Ias a lattice clathrate. Structure IIhas no analogs among the silver carboxylates. It simultaneously contains silver atoms with coordination numbers varying from 2 to 4.  相似文献   

16.
17.
The reaction for CH3CH2+N(4S) was studied by ab initio method. The geometries of the reactants, intermediates, transition states and products were optimized at MP2/6-311+G(d,p) level. The corresponding vibration frequencies were calculated at the same level. The single point calculations for all the stationary points were carried out at the QCISD(T)/ 6-311+G(d,p) level using the MP2/6-311+G(d,p) optimized geometries. The results of the theoretical study indicate that the major products are the CH2CH2+3NH and H2CN+CH3, and the minor products are the CH3CHN+H in the reaction. The majority of the products CH2CH2+3NH are formed via a direct hydrogen abstraction channel. The products H2CN+CH3 are produced via an addition/dissociation channel. The products CH3CHN+H are produced via an addition/dissociation channel.  相似文献   

18.
胡宁海  徐吉庆 《结构化学》1991,10(2):117-120
<正> Fe_4S_4[SC(CH_3)_3]_4[(C1H_9)_2,Mr=1193. 23,tetragonal,142d,a = 23. 272(2), c= 13. 080(5) A ,V=7084(3) A3,Z=4,DC=1. 12g·cm-3,UUUU(MoKa) = 10. 8cm-1,F(000) = 2568,R=0. 058 for 1005 observed reflections. The cluster anion contains a cubane-type Fe4S4 core compressed along the 4 axis which is crystallographically imposed. Compared to other salts with different cations ,the core is subject to slight structural distortions in different crystalline environments and crystallographic symmetry of the anion is related to that of the cation.  相似文献   

19.
吴鼎铭  黄小荥 《结构化学》1994,13(5):385-388
SynthesisandStructureof[HOCH_2CH_2N(CH_3)_3]_4[Cu_4OCl_(10)]WuDing-Ming;HuangXiao-Ying;ZhuangHong-Hui(StateKeyLaboratoryofStruct?..  相似文献   

20.
The reaction in THF of Na2[Fe(CO)4·xTHF with InBr3 in an approximate 3.5:1 molar ratio affords the new [In{Fe(CO)4}3]3− trianion, which has been isolated as its trimethylbenzylammonium salt and structurally characterized by single-crystal X-ray diffraction studies. On oxidation with two equivalents of AgBF4 it stepwise affords the anions [In2Fe6(CO)24]x with x = 4 and 2, respectively. Its reaction with InBr3 gives species of the composition [InBr3−x{Fe(CO)4x}]x (x = 1,2), and the anion with the composition [InBr2{Fe(CO)4}] has been structurally characterized as the dimeric species [InBr2Br4{η-Fe(CO)4}2]2−.  相似文献   

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