title: Efficient enhancement of magnetic anisotropy by optimizing the ligand-field in a typically tetranuclear dysprosium cluster.
abstract: The perturbation to the ligand field around the lanthanide ion may significantly contribute to the magnetic dynamics of single molecule magnets. This can be demonstrated by two typical Dy4 cluster-based single molecular magnets (SMMs), [Dy4X2(μ3-OH)2(μ-OH)2(2,2-bpt)4(H2O)4]X2·2H2O·4EtOH (X = Cl and Br for and , respectively), which were constructed by using 3,5-bis(pyridin-2-yl)-1,2,4-triazole (2,2-bptH) as the polynuclear-chelating ligand. Alternating-current (ac) magnetic susceptibility measurements show that the energy barriers in complexes and were immensely enhanced by comparing with our previous work due to the optimization of the ligand field around Dy(III) ions. Remarkably, their high thermal active barriers at 190 K () and 197 K () under a zero applied external dc magnetic field are also among the highest within the reported tetranuclear lanthanide-based SMMs.
authors.affiliation: Key Laboratory of Synthetic Bioinorganic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China. tongml@mail.sysu.edu.cn.
authors.forename: Jiang
authors.initials: J
authors.lastname: Liu
authors.forename: Yan-Cong
authors.initials: YC
authors.lastname: Chen
authors.forename: Zhong-Xia
authors.initials: ZX
authors.lastname: Jiang
authors.forename: Jun-Liang
authors.initials: JL
authors.lastname: Liu
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Jia
authors.forename: Long-Fei
authors.initials: LF
authors.lastname: Wang
authors.forename: Quan-Wen
authors.initials: QW
authors.lastname: Li
authors.forename: Ming-Liang
authors.initials: ML
authors.lastname: Tong