摘要
合成了六个含氮杂环桥联配合物:[Ni(salal)_2(4,4’-bipy)]_n、[Ni(Et-dtp)_2(4,4’-bipy]_n、[Cu-(acac)_2(4,4’-bipy)]_n、[Cu(TTA)_2(pyz)]_n、[Cu(TTA)(Im)]_n和[Cu(Im)_2]_n,用元素分析、IR、MS、ESR和热重分析对它们的结构和性质作了表征.吡嗪配合物的晶体结构显示,吡嗪配位于拉伸八面体的轴向位置,桥联Cu(TTA)_2形成一维无限链状结构.变温磁化率表明,4,4’-联吡啶和吡嗪配合物的磁性遵从Curie-Weiss定律,分子内没有明显的磁交换作用.咪唑配合物中存在着较强的反铁磁性交换作用,磁交换常数分别为-75和-107cm^(-1).对4,4’-联吡啶、吡嗪和咪唑传递磁交换的性质作了讨论.
Six-polynuclear complexes bridged by N-heterocycle, of formula [ Ni(salal)2(4,4'-bipy)]n, [Ni(Et-dtp)2(4,4/-bipy)]n, [Cu(acac)2(4,4/-bipy)]n, [Cu(TTA)2(pyz)]n, [Cu(TTA)(Im)]n and [Cu(Im)2]n, were synthesized and characterized by elemental analysis, IR, MS, ESR and thermogravimetric analysis, Crystal structure analysis has proved that the complex [Cu(TTA)2(pyz)]n has one-dimensional infinite linear structure. The local coordination geometry around Cu(Ⅱ) is a distorted octahedron. The variable-temperature magnetic susceptibility determinations show that the magnetic properties of 4,4'-bipyridine and pyrazine bridging complexes obey the Curie-Weiss law. The imidazole complexes have strong antiferromagnetic interactions, the parameters 2J=-75cm-1 for [Cu(TTA)(Im)]n and -107cm-1 for [Cu(Im)2]n. Magnetic experimental data are discussed in the relation to the structures of 4,4'-bipyridine, pyrazine and imidazole. It is shown that 4,4'-bipyridine is not a good bridge for propagating a magnetic exchange interaction between metal ions.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1995年第9期847-854,共8页
Acta Chimica Sinica
基金
国家科委攀登计划
国家自然科学基金资助课题
