材料期刊网

以对苯二甲酸根(TPHA)为桥联配体.分别端接4.4＇-二甲基-2.2＇-联吡啶(Me 2bpy)，2.9-二甲基-1.10-邻菲哕啉(Me2phen)和5-氯-1，10-邻菲哕啉(Cl-phen).合成了3种新的双核铬(Ⅲ)配合物[Cr2-(TPHA)(Me2bpy)4](NO3)4(1)，[Cr2(TPHA)(Me2phen)4](NO3)4(2)和[Cr 2(TPHA)(Clphen)4](N)3)4(3).经元素分析、摩尔电导和磁性测定以及红外光谱和电子光谱等手段，推定这些配合物具有TPHA桥联双核铬(Ⅲ)结构，其中，每个铬(Ⅲ)离子处于畸变八面体配位环境.测定了配合物(1)的变温磁化率(4～300 K)，其数值用最小二乘法和从自旋Hamiltonian算符(H=-2JS^1S^2)导出的磁方程拟合，求得交换积分为-2.98 cm-1，结果表明双核配合物中金属离子间存在弱的反铁磁自旋交换作用.

Three new terephthalato-bridged binuclear chromium (Ⅲ) complexes with the formula [-Cr2(TPHA)L4](NO3)4, where L stands for 4,4＇-dimethyl-2,2＇-bipyridine(Me2bpy); 2,9-dimethyl[-Cr2(TPHA)L4](NO3)4, where L stands for 4,4＇-dimethyl-2,2＇-bipyridine(Me2bpy); 2,9-dimethyl1,10-phenanthroline (Me2phen) and 5-chloro-1,10-phenanthroline (Clphen), repectively and TPHA respresents the terephthalate dianions, have been synthesized and characterized. Based on the elemental analyses, molar conductance and magnetic moments measurements, and spectroscopic studies, extended TPHA-bridged structures consisting of two chromium (Ⅲ) ions, each in an octahedral environment are proposed for these complexes. The variable temperature magnetic susceptibility of was determined at 4～300 K [Cr2(TPHA)(Me2bpy)4](NO3)4 and the obtained data were simulated by the least square fitting and the equation based on the spin Hamiltonian operator,H^=-2JS^1S^2, where the exchange integral J=-2.98 cm-1. The result indicates the presence of a weak antiferromagnetic spin-exchange interaction between the metal ions in the binuclear complex