化学学报 ›› 2008, Vol. 66 ›› Issue (12): 1429-1434. 上一篇    下一篇

研究论文

新型二维异核配位聚合物{[NdBi(cydta)(NO3)2(H2O)4]•2.5H2O}n的 晶体结构与热分解

蒋琪英a 邓洪权a 胡亚敏a 沈 娟a,b 钟国清*,a 胡宁海c   

  1. (a西南科技大学化学系 绵阳 621010)
    (b四川大学分析测试中心 成都 610064)
    (c中国科学院长春应用化学研究所 长春 130022)
  • 投稿日期:2007-10-08 修回日期:2008-01-07 发布日期:2008-06-28
  • 通讯作者: 钟国清

Crystal Structure and Thermal Decomposition of a 2D Heterometallic Coordination Polymer {[NdBi(cydta)(NO3)2(H2O)4]•2.5H2O}n

JIANG, Qi-Ying a DENG, Hong-Quan a HU, Ya-Min a SHEN, Juan a,b
ZHONG, Guo-Qing *,a HU, Ning-Hai c   

  1. (a Department of Chemistry, Southwest University of Science and Technology, Mianyang 621010)
    (b Analytical & Testing Center, Sichuan University, Chengdu 610064)
    (c Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022)
  • Received:2007-10-08 Revised:2008-01-07 Published:2008-06-28
  • Contact: ZHONG, Guo-Qing

由Bi(Hcydta)•5H2O和Nd(NO3)•6H2O按1︰1的物质的量比, 在水溶液中合成了含Bi(III)-Nd(III)的异核配位聚合物{[(NO3)Nd(H2O)4(μ3-cydta)Bi(μ-ONO2)]•2.5H2O}n. 用元素分析、红外光谱、热重-差热和X射线单晶衍射等手段对标题配合物的组成和结构进行了表征. 该配合物属三斜晶系, 空间群 , 晶胞参数: a=0.9235(3) nm, b=1.0902(4) nm, c=1.4253(5) nm, α=71.840(4)°, β=86.877(4)°, γ=76.991(4)°, Z=2, Mr=936.65, V=1.3284(8) nm3, Dc=2.342 g• cm-3, μ=8.646 mm-1, F(000)=900, 最终偏离因子R1=0.0406, wR2=0.1124. 在该配合物中, 铋(III)与配体cydta4-的4O2N和1个硝酸根中1个O原子以及邻位分子的硝酸根形成8配位的畸变双帽三棱柱. 钕(III)与4个水分子的O, 1个硝酸根中2个O以及来自3个不同配体cydta4-的桥联羧基O结合, 形成9配位的三帽三棱柱构型. 羧酸根在Bi—Nd和硝酸根在Bi—Bi间的桥联作用, 使得整个配合物分子连接成无限二维框架结构. 热分析以及分解产物的红外光谱表明配合物热分解经历脱水、配体热分解、硝酸盐转变成氧化物等多步连续分解过程, 最后在625 ℃失重恒定.

关键词: 杂核配合物, 铋(III), 钕(III), 氨基多羧酸, 晶体结构

A Bi(III)-Nd(III) heterometallic coordination polymer, {[(NO3)Nd(H2O)4(μ3-cydta)Bi- (μ-ONO2)]•2.5H2O}n, was synthesized by Bi(Hcydta)•5H2O and Nd(NO3)•6H2O at a molar ratio of 1︰1 in distilled water (cydta=trans-cyclohexylene-1,2-diaminetetraacetate). The compound was characterized by elemental analysis, FT-IR, TG-DSC and X-ray single crystal diffraction. It crystallizes in the triclinic system, space group with a=0.9235(3) nm, b=1.0902(4) nm, c=1.4253(5) nm, α=71.840(4)°, β=86.877(4)°, γ=76.991(4)°, Z=2, Mr=936.65, V=1.3284(8) nm3, Dc=2.342 g•cm-3, μ=8.646 mm-1, F(000)=900, R1=0.0406, and wR2=0.1124. In this complex, Bi atom is octahedrally coordinated by four carboxyl O atoms and two amido N atoms from a single cydta4- anion, and two O atoms from different two anions, forming a distorted bicapped trigonal prism geometry. Nd atom is bonded to four O atoms from four H2O molecules, two O atoms from one anion, and three O atoms from three bridging carboxylate groups belonging to different cydta4- anions, resulting in nine coordination number with a tricapped trigonal prism geometry. The bridging cydta4- between Bi—Nd atoms and between Bi—Bi atoms result in a novel infinite 2D network structure. FT-IR spectrum and DSC indicate that thermal decomposition proceeded in several stages: dehydration, pyrolysis of ligand, and final decomposition of salt, and the residue is oxide in the formula BiNdO3 at the temperature of 625 ℃.

Key words: heteronuclear complex, bismuth(III), neodymium(III), aminopolycarboxylate ligand, crystal structure