摘要
合成了分子式为[Ln_2(phen)_2L],phen=C_(12)H_8N_2[A Ln=Nd,L=(CH_3COO)_4(ONO_2)_2,B Ln=S_m,L=(C_6H_5COO)_6,C Ln=Eu,L=(C_6H_5COO)_6]_3种同双核配合物.用X射线四圆衍射仪测定了3种化合物的结构.在化合物A分子中,2个Nd(Ⅲ)原子由4个CH_3COO^-基团桥联,以phen和ONO_2^-为端基,构成了一个具有C_2对称性的双核分子配合物B和C具有完全相同的结构,它们是以4个苯甲酸根为桥,2个phen和2个C_6H_5COO^-为端基的中心对称双核分子,其中6个苯甲酸根的成键状态可分为3种状况.在3种化合物中,每个Ln均为9配位,呈不规则多面体.Ln-Ln距离,A为0.397nm,B和C均为0.405nm.测定了各配合物的变温磁化率,通过对磁性质研究,发现化合物A在低温下具有反铁磁物质行为.并由理论拟合,求得了磁参数g,J值.
Three binuclear Ln(Ⅲ) complexes with formulas [Ln2(phen)2L] , [phen = C12H8N2, A Ln = Nd, L=(CH3COO)4(ONO2); B Ln=Sm, L= (C6H5COO)6; C Ln=Eu, L= (C6H5COO)6] have
been synthesized. Their molecular structures and crystal structures have been determined by X-ray
diffraction analysis. In the complex A, two Nd(Ⅲ) ions are bridged by four CH3COO- groups and
coordinated to two phen and two ONO2- groups, giving a binuclear Nd2(phen)2(ONO2)2(CH3COO)4 unit. This molecule possesses C2 point group symmetry. The structures of the complexes B and C are completely same. They are centrosymmetric binuclear molecules with four benzoate bridges and two phen and two C6H5COO- ligands. Every Ln atom is 9-coordinated in an irregular polyhedron. The distance of Ln- Ln is 0.397nm for complex A and 0.405nm for complexes B and C. Cryomagnetic investigations reveal a weak antiferromagnetic property only for the complex A.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1999年第9期961-966,共6页
Acta Chimica Sinica
基金
国家自然科学基金(59572039)
辽宁省自然基金资助项目
关键词
镧系
稀土元素
双核
配合物
晶体结构
磁性
lanthanide elements, binuclear complex, crystal structure, magnetism
