title: Weak Ligand-Field Effect from Ancillary Ligands on Enhancing Single-Ion Magnet Performance.
abstract: A series of bis-pentamethylcyclopentadienyl-supported Dy complexes containing different ancillary ligands were synthesized and characterized. Magnetic studies showed that 1 Dy [Cp*2 DyCl(THF)], 1 Dy' [Cp*2 DyCl2 K(THF)]n , 2 Dy [Cp*2 DyBr(THF)], 3 Dy [Cp*2 DyI(THF)] and 4 Dy [Cp*2 DyTp] (Tp=hydrotris(1-pyrazolyl)borate) were single-ion magnets (SIMs). The 1D dysprosium chain 1 Dy' exhibited a hysteresis at up to 5 K. Furthermore, 3 Dy featured the highest energy barrier (419 cm(-1) ) among the complexes. The effects of ancillary ligands on single-ion magnetic properties were studied by experimental, ab initio calculations and electrostatic analysis methods in detail. These results demonstrated that the QTM rate was strongly dependent on the ancillary ligands and that a weak equatorial ligand field could be beneficial for constructing Dy-SIMs.
authors.affiliation: Beijing National Laboratory of Molecular Science, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
authors.forename: Yin-Shan
authors.initials: YS
authors.lastname: Meng
authors.affiliation: Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing, 210023, P. R. China. zhangyiquan@njnu.edu.cn.
authors.forename: Yi-Quan
authors.initials: YQ
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory of Molecular Science, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
authors.forename: Zhe-Ming
authors.initials: ZM
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory of Molecular Science, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China. wangbw@pku.edu.cn.
authors.forename: Bing-Wu
authors.initials: BW
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory of Molecular Science, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China. gaosong@pku.edu.cn.
authors.forename: Song
authors.initials: S
authors.lastname: Gao
keywords: ab initio calculations; ancillary ligands; magnetic anisotropy; magnetic properties; single-ion magnets