The high-spin ground state of quadridentate salicylaldehyde Schiff-base complexes of cobalt(II) in N-heterocyclic solvents
The high-spin ground state of quadridentate salicylaldehyde Schiff-base complexes of cobalt(II) in N-heterocyclic solvents
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N-杂环溶剂中钴(II)四齿水杨醛席夫碱配合物的高自旋基态
DOI：
10.1039/dt9830002281
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
M. Iwaizumi
中科院分区：
文献类型：
--
作者：
K. Migita;M. Chikira;M. Iwaizumi
通过 e.s.r.、n.m.r. 和磁化率测量，对钴 (II) 的四齿水杨醛席夫碱配合物在含有 N-杂环碱的溶液中形成了高自旋基态 (S=) 的物质。研究发现，双齿碱基 1,10-菲咯啉也能产生类似的高自旋物质。高自旋物质被证明是具有六配位结构的基础加合物。磁化率测量表明，22% 的 NN′- 亚乙基双（水杨亚胺基）钴 (II) 在 295 K 下以高自旋碱基双加合物形式存在于吡啶中。发现形成这种高自旋物质的热力学参数 ΔH⊖ 为 –4.25 × 103J mol–1。随着温度降低，高自旋物质的数量增加。 1H nmr 各向同性位移分析揭示高自旋物种中不成对电子自旋主要通过σ轨道离域。
Formation of species with a high-spin ground state (S=) has been observed by e.s.r., n.m.r., and magnetic susceptibility measurements for quadridentate salicylaldehyde Schiff-base complexes of cobalt(II) in solution containing N-heterocyclic bases. It was found that a bidentate base, 1,10-phenanthroline, also gave similar high-spin species. The high-spin species were shown to be the base adducts having a six-co-ordinate structure. Magnetic susceptibility measurements revealed that 22% of NN′- ethylenebis(salicylideneiminato)cobalt(II) exists as the high-spin base di-adduct in pyridine at 295 K. The thermodynamic parameter ΔH⊖ for the formation of this high-spin species was found to be –4.25 × 103J mol–1. The amount of the high-spin species increased as the temperature decreased. The analysis of the isotropic shifts in 1H n.m.r. Revealed that the unpaired electron spins in the high-spin species mainly delocalize through σ orbitals.