Magnetization Slow Dynamics in Ferrocenium Complexes
Magnetization Slow Dynamics in Ferrocenium Complexes
复制标题
DOI：
10.1002/chem.201900799
复制
发表时间：
2019-07-17
影响因子：
4.3
通讯作者：
Smith, Jeremy M.
中科院分区：
文献类型：
--
作者：
Ding, Mei;Hickey, Anne K.;Smith, Jeremy M.
报道了一系列二茂铁配合物[Fe(eta(5)-C5R5)(2)](+) （R=Me, Bn）的单分子磁体（SMM）性质。在外加直流电场的作用下，揭示了[Fe(eta(5)-C5Me5)(2)]BArF的缓慢磁化动力学。多参考量子力学计算表明，在基态和第一激发态之间存在很大的能量差，不包括通常调用的热激活（类奥尔巴赫）弛豫机制。相反，对弛豫时间的详细分析表明，直接过程和拉曼过程都对SMM的性质负责。同样，体积庞大的二铁配合物[Fe(eta(5)-C5Bn5)(2)]BF4和[Fe(eta(5)-C5Bn5)(2)]PF6也表现出磁化慢动力学，然而，在这些类似体系中可以清楚地检测到额外的弛豫过程。
The single-molecule magnet (SMM) properties of a series of ferrocenium complexes, [Fe(eta(5)-C5R5)(2)](+) (R=Me, Bn), are reported. In the presence of an applied dc field, the slow dynamics of the magnetization in [Fe(eta(5)-C5Me5)(2)]BArF are revealed. Multireference quantum mechanical calculations show a large energy difference between the ground and first excited states, excluding the commonly invoked, thermally activated (Orbach-like) mechanism of relaxation. In contrast, a detailed analysis of the relaxation time highlights that both direct and Raman processes are responsible for the SMM properties. Similarly, the bulky ferrocenium complexes, [Fe(eta(5)-C5Bn5)(2)]BF4 and [Fe(eta(5)-C5Bn5)(2)]PF6, also exhibit magnetization slow dynamics, however an additional relaxation process is clearly detected for these analogous systems.