具有易轴型磁各向异性的六配位钴（II）配合物的场诱导单离子磁体行为

Field-induced single-ion magnet behaviour of a hexacoordinated Co(ii) complex with easy-axis-type magnetic anisotropy.

作者信息

Tupolova Yulia P, Shcherbakov Igor N, Popov Leonid D, Lebedev Vladimir E, Tkachev Valery V, Zakharov Konstantin V, Vasiliev Alexander N, Korchagin Denis V, Palii Andrei V, Aldoshin Sergey M

机构信息

Department of Chemistry, Southern Federal University, 7, Zorge Str., Rostov-on-Don, 344090, Russia.

出版信息

Dalton Trans. 2019 May 21;48(20):6960-6970. doi: 10.1039/c9dt00770a.

DOI:10.1039/c9dt00770a

PMID:31041973

Abstract

A coordination compound with the composition [CoLCl2]·H2O (L = bis-condensation product of diacetyl and 2-hydrazinyl-4,6-dimethylpyrimidine) was synthesized, in which the Co(ii) ion was hexacoordinated. Under applied DC fields, this compound exhibited single-ion magnet behavior. Two relaxation processes were observed when increasing the applied magnetic field from 1000 to 3200 Oe. The first relaxation (high-frequency) was observed both at 1000 Oe and 3200 Oe, while the second relaxation was only registered under a field of 3200 Oe at low frequencies (<1 Hz) and low temperatures (<5 K). Modeling of the magnetic DC properties using the Griffith Hamiltonian accompanied by quantum chemical calculations revealed easy-axis-type magnetic anisotropy with weak rhombic contributions.

摘要

合成了一种组成为[CoLCl₂]·H₂O（L = 二乙酰与2 - 肼基 - 4,6 - 二甲基嘧啶的双缩合产物）的配位化合物，其中Co(ii)离子为六配位。在施加直流磁场时，该化合物表现出单离子磁体行为。当施加磁场从1000奥斯特增加到3200奥斯特时，观察到两个弛豫过程。第一个弛豫（高频）在1000奥斯特和3200奥斯特时均被观察到，而第二个弛豫仅在3200奥斯特的磁场下、低频（<1赫兹）和低温（<5开尔文）时被记录到。使用格里菲斯哈密顿量对直流磁性质进行建模并结合量子化学计算，揭示了具有弱菱形贡献的易轴型磁各向异性。