Department of Chemistry, Texas A&M University, College Station, TX 77843 (USA) http://www.chem.tamu.edu/rgroup/dunbar/
Angew Chem Int Ed Engl. 2015 May 11;54(20):5864-8. doi: 10.1002/anie.201411190. Epub 2015 Mar 24.
Given the recent advent of mononuclear single-molecule magnets (SMMs), a rational approach based on lanthanides with axially elongated f-electron charge cloud (prolate) has only recently received attention. We report herein a new SMM, [Li(THF)4[Er{N(SiMe3)2}3Cl]⋅2 THF, which exhibits slow relaxation of the magnetization under zero dc field with an effective barrier to the reversal of magnetization (ΔEeff/kB =63.3 K) and magnetic hysteresis up to 3 K at a magnetic field sweep rate of 34.6 Oe s(-1). This work questions the theory that oblate or prolate lanthanides must be stabilized with the appropriate ligand framework in order for SMM behavior to be favored.
鉴于单核单分子磁体（SMM）的最新出现，最近才开始关注基于轴向拉长的 f 电子电荷云（扁长形）的镧系元素的合理方法。我们在此报告了一种新的 SMM，[Li(THF)4[Er{N(SiMe3)2}3Cl]⋅2 THF，它在零直流场下表现出磁化缓慢弛豫，具有有效的磁反转势垒（ΔEeff/kB =63.3 K）和磁滞，在磁场扫描速率为 34.6 Oe s(-1)时，温度高达 3 K。这项工作对理论提出了质疑，即扁长形或扁长形镧系元素必须通过适当的配体框架稳定下来，才能有利于 SMM 行为。
