摘要
合成了4种以氯醌酸阴离子为桥联配体的Ni(Ⅱ)单核和双核配合物,经元素分析、IR、电子光谱、磁化率测定进行了表征。发现其μeff值随温度降低先出现极大,后又复变小。在考虑到分子间相互作用和单离子零场分裂影响等因素后,用修正的Heisenberg模型进行处理,结果表明分子内Ni(Ⅱ)离子间存在铁磁性磁交换作用,而分子间则为反铁磁性磁交换作用。
Four new nicke(Ⅱ) complexes containing the dianions of chloranilic acids(CA) which act as the bridging ligand in these complexes were synthesized, namely [Ni(phen)2CA] 3H2O(1; phen =o-phenanthroline), [Ni2(phen)4CA](ClO4)2 3H2O(2), [Ni(bpy)2CA] H2O(3; bpy=2,2'-bipyridyl) and [Ni2(bpy)4CA](ClO4)2 2H2O(4). They have been characterized by elemental analyses, IR, electronic spectra, ESR, susceptibility and variable-temperature magnetic susceptibility. Ni (Ⅱ) might display distorted octahedral coordination in the complexes. The variable-temperature magnetic susceptibilities of (2) and (4) were measured (4~300K). Based on the fact that as the temperature is lowered,μell, gradually increases until a maximum is reached and then decreased, considering the combined effects of single-ion zero-field splitting(D) and interdimer interaction(Z' J' ), the observed data were fitted to those from a modified Heisenberg model. The obtained parameters: J = 100. 34, Z' J' = - 0. 382 for the complex(2) ; J = 69. 66, Z' J' = - 0. 382 for the complex(4). The results indicate that there is a ferromagnetic intracluster interaction (positive J) and antiferromagnetic interdimer interaction (negative Z' J1 )
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
1991年第4期427-430,共4页
Chemical Journal of Chinese Universities
基金
国家自然科学基金
