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1.
采用高温固相反应和化学气相传输法合成三硒化二铒。晶体属于四方晶系,M_r=571.40,空间群为P4/nmm,a=3.984(1),c=8.228(3),V=130.59(7),Z=1,D_c=7,27g/cm ̄3,F(000)=238,μ(MoKα)=528.86cm ̄(-1),对于187个I≥3σ(I)的独立衍射点,最后偏离因子R=0.066,R_w=0.078。化合物Er_2Se_3的晶体结构是由Er配位多面体的双层状结构通过共用Se(2)原子,沿c轴方向堆积而形成的三维结构。  相似文献   
2.
合成了标题化合物,在已测晶体结构的基础上,利用含组态作用的INDO/S方法计算了其他电子能带结构;利用态求和方法计算了微结构分子的线性极化率及其晶体的平均折射率。分析结果表明,价带主要由B^3^+和O^2^-离子的价轨道的贡献,导带底部主要由Ca^2^+离子轨道的贡献,从O^2^-离子到Ca^2^+离子的电荷转移对线性极化率起主要贡献。  相似文献   
3.
1 INTRODUCTION Molybdenum(I) compounds, in particular Mo(I)-SR compounds, are rare amongst numerous Mo compounds. So far, only the following compounds [Mo2(CO)8-n(SR)2(CH_3CN)n] (R = C6H5, CH_2CO2Et, n = 0, 2)[1~5] have been reported in the literature. Recently, we make an effort to develop investigations on Mo(I) compounds on the basis of preparing new Mo(I) compounds by introducing different functional ligands into Mo2(SR)2(CO)8, then determining their structures and measur…  相似文献   
4.
0引言由于金属和有机配体的超分子构建的拓扑多样性和在功能材料方面的潜在应用,在近几年引起化学工作者的浓厚兴趣,成为一个热门的研究领域[1 ̄5]。众所周知,这类聚合物具有许多特殊的性能,在新功能材料如选择性催化、分子识别、超高纯度分离材料、光电材料、新型半导体材料、磁性材料等方面的开发中显示了诱人的应用前景[6,7]。在早期合成这类超分子配位聚合物时,人们常使用含N配体,如4,4′-联吡啶,1,2-双(4-吡啶)乙烷等配体[8]。近几年来,人们常选择含O的芳香羧酸及其衍生物作配体。如具有3D穿插结构的Zn化合物{[Zn(dpe)(OH-BDC)](d…  相似文献   
5.
The novel complex {[Co(bipy)(azpy)2(NCS)2]·H2O}n (where bipy=4,4′-bipyridine, azpy=4,4′-azobisp- yridine) has been synthesized and characterized by elemental analyses, IR, UV, thermal analyses, and vari-able-temperature magnetic susceptibility. The crystal (C32H26CoN12OS2, Mr=717.70) belongs to the orthorhombic, space group Pnna, a=2.21312(16)nm, b=1.40403(10)nm, c=1.14237(8)nm, V=3.5497(4)nm3, Z=4, Dc=1.343g·cm-3, μ=0.645mm-1, F(000)=1476, and final R1=0.0691, wR2=0.1129 for 231 parameters and 1674 observed reflections [I >2.00σ(I)]. The Co(Ⅱ) atom is, in a distorted octahedral geometry, coordi-nated by six nitrogen atoms from two bridging bipy, two monodentate azpy, and two thiocyanate groups. The bridging ligand bipy links Co(Ⅱ) atoms to form the infinite “rod" with terminal coordination azpy ligand acting as sidearms. Unprecedented three parallel interpenetrating two-dimensional (4,4) networks and novel infinite triple helices are formed via hydrogen-bonding interactions. CCDC: 155588.  相似文献   
6.
Four heterodinuclear cryptates [EuML(dmf)](ClO(4))(2) (M=Ca, Cd, Ni, Zn) were synthesized by a two-step method (L denotes deprotonated anionic cryptand synthesized by condensation of tris(2-aminoethyl)amine with 2,6-diformyl-4-chlorophenol). The ES-MS spectra of the four cryptates and the crystal structure of [EuNiL(dmf)](ClO(4))(2) x MeCN confirm that a strict dinuclear Eu(III)-M(II) entity exits in the cryptates. The cyclic voltammetry and luminescence spectral investigations indicate that the introduction of second metal ions into the mononuclear Eu(III) cryptate result in a negative shift of the redox potential of Eu(III) and a change in luminescence intensity of Eu(III). The cryptate [EuML(dmf)](ClO(4))(2) was shown to quench the emission of Eu(III) when M=Ni and to enhance the emission of Eu(III) when M=Ca, Cd, and Zn in the sequence: mononuclear相似文献   
7.
The synthesis as well as crystal and molecular structure of [Bi(C5H4NOS)3] are reported. The complex crystallizes in the monoclinic system, space group P21/n with lattice parameters a = 9.6521(3) Å, b = 10.0659(4) Å, c = 18.4484(7) Å, = 102.13(6)°, and D calc = 2.227 Mg · m–3 for Z = 4. It is clear from the packing diagram that the title compound is a dimer via the secondary coordination. Surrounding Bi atom, three five-membered ring planes (Bi,O,N,C,S) make a dihedral angle of 55.91, 54.72, and 26.13° respectively. The whole crystal presents a three-dimensional network structure as each molecule produces four weak C–H O hydrogen bonds and a weak C–H S hydrogen bond.  相似文献   
8.
ZnCl2, PhONa和Et4NCl稨2O在乙腈溶剂中反应合成了一种二核锌配合物[Et4N]2[Zn2(OPh)2Cl4]。X射线衍射结果表明,晶体属单斜晶系,C2/m空间群,晶胞参数 a = 14.1366(2), b=13.6985(5), c=9.3308(3)牛?107.851(2)o, V=1719.92(9)?,C28H50O2N2Zn2Cl4,Mr=721.24,Z=2,Dx=1.393g/cm3,μ(MoKα)=1.732mm—1,F(000)=756, R=0.0552, wR=0.1534, S=1.027。 配合物是由2个阳离子Et4N+和1个阴离子[Zn2(OPh)2Cl4]2—组成。阴离子[Zn2(OPh)2Cl4]2—包含着1个中心Zn2O2菱形平面。配合物中的2个锌原子通过2个苯酚中的氧原子桥连,每个锌原子还与2个氯原子配位形成变形四面体结构。  相似文献   
9.
10.
陈久桐  郭国聪 《结构化学》1996,15(3):231-234
通过(1)LnOCl/V_2O_5,(2)LnCl3/V及(3)LnOCl/LnCl/V_2O_5/V的高温固态化学反应,得到两种稀土钒酸盐:Ln_6V_3Cl_(10)O_(12)(Ln=La)及Ln_4V_5Si_4O_(22)(Ln=La~Nd)。La_6V_3O_(10)O_(12)晶体呈浅色透明片状,其结构可认为是由[La_3(VO_4)_3Cl]单元插入到LaCl3结构单元中而形成的,在结构中沿c轴方向存在一系列截面积为19.1的空洞。Ln_4V_5Si_4O_(22)(Ln=La,Ce,Pr,Nd)晶体呈,黑色针状,其结构可认为是由交替的稀土钒硅酸盐薄层及钒氧金红石层沿c轴堆叠而表现为准二维Chevkinite型结构。  相似文献   
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