Yang Rui-Chong, Wang Dan-Ru, Liu Jun-Liang, Wang Yu-Fei, Lin Wei-Quan, Leng Ji-Dong, Zhou Ai-Ju
School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials, Guangzhou University, Guangzhou Higher Education Mega Center, No. 230 Wai Huan Xi Road, Guangzhou, 510006, P. R. China.
Key Lab of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, P. R. China.
Chem Asian J. 2019 May 2;14(9):1467-1471. doi: 10.1002/asia.201900280. Epub 2019 Apr 4.
Two isostructural mononuclear Co complexes, [Co(xantpo)(NCE) ] (E=S (1) and O (2); xantpo=9,9-dimethyl-4,5-bis(diphenylphosphoryl) xanthene), supported by a bidentate phosphine oxide ligand are reported. The cobalt complexes exhibit characteristic tetrahedral structures coordinated with two oxygen and two nitrogen atoms. Magnetic property measurements show their similar static magnetic behaviours but very different dynamic magnetic behaviours. Both complexes show field-induced slow magnetic relaxation behaviours, but the relaxation of 2 is much slower than that of 1. Fittings to the magnetic data and ab initio CASSCF calculations reveal significant changes in the zero field splitting (ZFS) parameters (D and E), which can be attributed to the small geometrical changes of the Co ions and the different ligand field strength of the two terminal ligands.
报道了由双齿氧化膦配体支撑的两个同构单核钴配合物[Co(xantpo)(NCE)]（E = S（1）和O（2）；xantpo = 9,9-二甲基-4,5-双（二苯基磷酰基）占吨）。钴配合物呈现出与两个氧原子和两个氮原子配位的特征四面体结构。磁性测量表明它们具有相似的静态磁行为，但动态磁行为非常不同。两种配合物都表现出场诱导的慢磁弛豫行为，但2的弛豫比1慢得多。对磁性数据的拟合和从头算CASSCF计算揭示了零场分裂（ZFS）参数（D和E）的显著变化，这可归因于钴离子的微小几何变化以及两个末端配体不同的配体场强度。
