高等学校化学学报

• 研究论文 • 上一篇    下一篇

羧酸桥联镍(Ⅱ)四氮杂环配合物的合成、晶体结构与磁性

嵇从民, 张冰, 崔爱莉, 寇会忠   

  1. 清华大学化学系, 北京 100084
  • 收稿日期:2008-01-28 修回日期:1900-01-01 出版日期:2008-06-10 发布日期:2008-06-10
  • 通讯作者: 崔爱莉

Synthesis, Structure and Magnetic Property of a Terephthalato-bridged Nickel(Ⅱ) Tetraazamacrocyclic Complex

JI Cong-Min, ZHANG Bing, CUI Ai-Li*, KOU Hui-Zhong
  

  1. Department of Chemistry, Tsinghua University, Beijing 100084, China
  • Received:2008-01-28 Revised:1900-01-01 Online:2008-06-10 Published:2008-06-10
  • Contact: CUI Ai-Li

摘要: 以对苯二甲酸根为桥联基团合成了一个新的镍(Ⅱ)四氮杂环羧酸桥联配合物[Ni(L)tp](L=5-苯甲基-4,6-二甲基-1,3,7,10-四氮杂环十四烷). X射线单晶衍射结果显示, Ni(Ⅱ)离子呈扭曲的八面体构型. 每个对苯二甲酸阴离子tp2-按照反式单齿桥联的模式连接两个Ni(Ⅱ)离子, 每个Ni(Ⅱ)离子反式桥连两个tp2-配体, tp2-和Ni(Ⅱ)离子交替排列形成一维链状配位聚合物. 磁性研究结果表明, 配合物的χmT在低温时略有减小, 根据结构分析将其归因于链内tp2-传递的弱反铁磁耦合和八面体Ni(Ⅱ)的零场分裂.

关键词: 配合物, 羧酸桥联, 磁性, 镍, 四氮杂环

Abstract: A new terephthalato-bridged nickel(Ⅱ) complex with a teraazamacrocyclic ligand, [Ni(L)tp](L=5-benzyl-4,6-bimethyl-1,3,7,10-tetraaza-cyclotetradecane) was synthesized and characterized. On the basis of the X-ray crystallographic study, each Ni(Ⅱ) ion lies in a distorted octahedral environment, and the terephthalato ligand bridges two Ni(Ⅱ) ions in a trans fashion. The [Ni(L)]2+ and the tp2- groups are alternatively arranged yielding a one-dimensional coordination polymer. Magnetic measurements show that the decrease of χmT below 25 K gave a Weiss constant of θ=-0.49 K. This behavior may be due to a very weak intrachain magnetic superexchange through the tp2- bridge, a weak interchain exchange interaction and the zero-field splitting(ZFS) of octahedral Ni(Ⅱ) ions.

Key words: Coordination compound, Terephthalato-bridge, Magnetic property, Nickel(Ⅱ), Teraazamacrocycle

中图分类号: 

TrendMD: