首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
[Be(NCS)2(C5H5N)2] was prepared and characterized by chemical analysis, FT-IR-analysis, and single crystal X-ray structure analysis. The crystals are orthorhombic with a = 829.30(10) pm, b = 1292.1(2) pm, c = 1313.40(10) pm, space group Pnma. Z = 4. The structure is built up from tetrahedra. Hydrogen bonding between the S-atom of one Be-N-bonded thiocyanate and 1.3-H-atoms of pyridine ligands yield a three dimensional network consisting of folded sheets.  相似文献   

3.
4.
5.
6.
IntroductionThe 1 ,2 - dicyanoethene- 1 ,2 - dithiolato anion isa bidentate ligand.It can form square- coplanarcomplexes with many transition metal ions and hasfound a lot of application in analytical chemistry,catalyst and biochemistry.In recent years,metalcomplexes containing mnt and its dithiolate analogligands have been extensively studied and have re-ceived considerable attention due to their potentialapplication in charge transfer and storage,molecu-lar metals,magnetic materials,supercon…  相似文献   

7.
8.
Polysulfonylamines. LXXXIV. Isotypic Structures in the Dimesylamide Complex Series [M(H2O)4{(CH3SO2)2N}2] (M?Mg, Ca, Ni, Cu, Zn, Cd) and [M(py)4{(CH3SO2)2N}2] (M?Ni, Cu, Zn, Cd) The crystal structures of the trans-octahedral complexes [M(H2O)4{(CH3SO2)2N}2] (M?Ca, Cd), in which the dimesylamide anion acts as a monodentate O-ligand and a tetrafunctional hydrogen bond acceptor, were determined by low-temperature X-ray diffraction. Both belong to an isotypic series (triclinic, space group P1 , Z = 1) that had previously been characterized for M?Mg, Ni, Cu and Zn (Z. Anorg. Allg. Chem. 1996 , 622, 1065). In this structure there exists an extended network of strong hydrogen bonds which is probably the underlying reason why the structure type surprisingly persists across the whole series. To support this explanation by indirect evidence from comparison with suitable structures devoid of strong hydrogen bonding, the analogous trans-octahedral complexes [M(py)4{(CH3SO2)2N}2] (M?Mn, Co, Ni, Cu, Zn, Cd) were prepared by treating M[(CH3SO2)2N]2 with pyridine, and the crystal structures of the Ni, Cu, Zn and Cd compounds were studied by low-temperature X-ray crystallography. As anticipated, the four pyridine complexes do not form an isotypic series but instead two isotypic pairs consisting of the Ni and Zn compounds (monoclinic, space group P21/n, Z =2) and of the Cu and Cd complexes (triclinic, space group P1, Z = 1). All molecules of the aqua and the pyridine complexes display crystallographic centrosymmetry. In the hydrates, the mean M? OH2 and the M? O(anion) distances are 232.6 and 232.7 pm for M ? Ca, 225.5 and 230.3 pm für M ? Cd. The mean M? N and the M? O(anion) bond lengths of the pyridine species amount to 211.8 and 213.1 pm for M ? Ni, 217.0 and 218.5 pm for M ? Zn, 232.8 and 234.4 pm for M ? Cd; the corresponding values for the severely Jahn-Teller distorted Cu complex are 203.6 and 254.5 pm. In the crystals of the pyridine complexes, each methyl group is connected through a weak C? H…?O bond to a sulfonyl oxygen atom of an adjacent molecule.  相似文献   

9.
10.
11.
王庆华  翁文  郭国聪 《结构化学》2004,23(8):932-935
用 HgI2 和 4,5-亚乙基二硫杂-1,3-二硫杂-2-硫酮 (C5H4S5)反应,合成一种二核汞配合物[Hg(C5H4S5)I2]2 1。X 射线衍射结果表明,晶体属于单斜晶系,C2/c 空间群,晶胞参数 a =21.6847(1),b = 8.5125(4),c = 15.6699(8),a=112.7850(1)°,V=2666.8(2) ?3。Mr = 1357.54,Z = 4,Dx = 3.381 g/cm3,ì = 16.913 cm–1,F(000) = 2400,R=0.0639,wR=0.1711,S=1.052。配合物 1 具有二聚体结构,2 个汞原子通过 2 个碘原子桥联,形成 1 个 Hg2I2菱形平面,汞原子周围的配位是四面体结构,通过分子间的硫…硫作用和碘…硫作用,形成准二维超分子网络。 S S S H g I I S S S S I I H g S  相似文献   

12.
13.
采用从头算Hartree-Fock(HF),M??ller-Plesset微扰(MP2),二级近似耦合簇(CC2)和密度泛函理论(DFT)方法,对IB族金属-乙烯配合物LM-C2H4(L=[N{(Me)C(Ph)N}2];M=Cu,Ag,Au)的几何结构、电子结构以及LM与C2H4之间的结合能进行了理论研究.MP2、CC2和密度泛函方法对C2H4配位前后C=C键长的变化情况都给出了正确的描述.电子结构分析显示LM与C2H4之间主要以C2H4→LM"σ-给予"和LM→C2H4"π-反馈"方式协同成键,这种成键方式使C2H4配体π轨道上的电子密度下降,π*轨道上的电子密度增加,并使得C=C键长增加、键能下降,从而达到活化C=C键的目的.自然电荷布居和能量分解分析显示LM-C2H4中的"σ-给予"作用弱于"π-反馈"作用,若使用"σ-给予"作用强于"π-反馈"作用的M+-C2H4体系作为LM-C2H4的简化模型进行理论研究是不合适的.LM-C2H4中金属原子M的改变对C=C键长、C2H4电荷布居以及LM与C2H4之间的结合能等性质影响显著.LAu与LCu、LAg相比其接受和反馈电子的能力最强,使C2H4配体π轨道电子密度减少的程度和π*轨道电子密度增加的程度也最大,因此LAu对C2H4中C=C键的活化效果最好.螯合配体取代基供、吸电能力的改变对上述性质的影响则非常有限.  相似文献   

14.
硫氰酸根的结构为N三C-S-,其两端的N原子和S原子分别有一对和三对孤对电子,因此,硫氰酸根可采用多种不同的配位模式与金属离子发生配位.硫氰酸根可作为单齿配体与一个金属离子配位,形成M-SCN或M-NCS的单核配合物,也可以作为桥联配体同时与两个、三个甚至四个金属离子配位形成多核配合物[1-3];另一方面,硫氰酸根是一个具有一定共轭性的偶极子,可传递磁相作用.因此,选择硫氰酸根作为桥联配体,将多个顺磁金属离子桥联形成一维、二维或三维结构的多核金属配合物分子,并研究它们的磁性已成为分子磁学的一个研究领域[4-6].本文仅报道标题配合物的合成与晶体结构.  相似文献   

15.
Cobalt cyclopentadienyl complexes incorporating a fumarate and a CO ligand (see picture) efficiently catalyze inter‐ and intramolecular [2+2+2] cycloadditions of alkynes, nitriles, and/or alkenes to give benzenes, pyridines, or 1,3‐cyclohexadienes. Unlike catalysts such as [CpCo(CO)2] or [CpCo(C2H4)2] (Cp=C5H5), they are air‐stable, easy to handle, compatible with microwave conditions, and do not necessarily require irradiation to be active.

  相似文献   


16.
Infrared spectra of Mn(NH3)2M(CN)4·2C6H5NH2 (M = Zn, Cd or Hg) are reported. The spectral data suggest that these compounds are similar in structure to Hofmann-Td-type clathrates.  相似文献   

17.
Volatile mixed-ligand compounds of Cd(i-Bu2PS2)2with Phen, 2,2"-Bipy, and 4,4"-Bipy were synthesized. Their single crystals were grown. X-ray diffraction data (a CAD4 diffractometer, MoK radiation, 2140 F hkl, R=0.0251) were used to determine the structure of [Cd(4,4"-Bipy)(i-Bu2PS2)2]. The crystals are mono-clinic: a= 14.678(3) Å, b= 11.866(2) Å, c= 19.655(4) Å, = 102.17(3)°, V= 3346(1) Å3, Z= 4, calcd= 1.364 g/cm3, space group C2/c. The structure is built from linear polymeric chains arranged along the [010] direction. The coordination polyhedron of the Cd atom is a distorted octahedron (4S + 2N). The thermal properties of these compounds, studied both in air and in vacuo, allow one to use them for preparing CdS films by chemical precipitation from the gas phase.  相似文献   

18.
19.
A new cadmium coordination polymer,[Cd(C14H10N3O5)2(C5H5N)2]n,has been synthesized by the reaction of 2-hydroxy-N'-(4-nitrobenzoyl)benzohydraizide with cadmium acetate in pyridine and ethanol mixture solution.Its molecular structure was characterized by elemental analysis,IR spectra and X-ray crystal structure determination.Crystal data for this compound:tetragonal,space group I41/a,Mr=871.10,a=16.960(6),b=16.960(6),c=28.612(6) ,V= 8230(4)3,Z=8,Dc=1.406 g·m-3 and F(000)=3536.the final R=0.0326,wR=0.0847 for 2682 observed reflections with I 2σ(I) and R=0.0460,wR=0.0896 for all reflections.In the molecular structure of the complex,the cadmium atoms are coordinated to four N and two O atoms forming a slightly distorted octahedral geometry.The intermolecular hydrogen bonds link the neighboring molecules to form a coordination polymer which was then evaluated for its anti-tumor activities against two kinds of cell lines (K562 and BGC) by MTT method.A preliminary bioactivity study indicates that the complex has distinct inhibitory effect on K562 cell lines.  相似文献   

20.
以大空阻的3.三甲基硅-吡啶-2-硫酚为配体,合成了2个单核镉、锌配合物,并用X射线单晶衍射法测定了其晶体结构.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号