Seeking magneto-structural correlations in easily tailored pentagonal bipyramid Dy(Ⅲ) single-ion magnets

• 作者: Guo-Zhang Huang Jie-Yu Zheng Jun-Liang Liu Ming-Liang Tong Si-Guo Wu Yan-Cong Chen Ze-Yu Ruan
• 来源期刊: 中国科学:化学（英文版）
• 年，卷（期）: 2020,（8）
• 所属期刊栏目: ARTICLES
• 页码范围: 1066-1074
• 页数: 9页
• 语种: 英文

摘要

Controlling molecular magnetic anisotropy via structural engineering is delicate and fascinating,especially for single-molecule magnets (SMMs).Herein a family of dysprosium single-ion magnets (SIMs) sitting in pentagonal bipyramid geometry have been synthesized with the variable-size terminal ligands and counter anions,through which the subtle coordination geometry of Dy(Ⅲ) can be finely tuned based on the size effect.The effective energy barrier (Ueff) successfully increases from 439 to 632 K and the magnetic hysteresis temperature (under a 200 Oe/s sweep rate) raises from 1 1 to 24 K.Based on the crystal-field theory,a semi-quantitative magneto-structural correlation deduced experimentally for the first time is revealed that the Ueff is linearly proportional to the structural-related value S02 corresponding to the axial coordination bond lengths and the bond angles.Through the evaluation of the remanent magnetization from hysteresis,quantum tunneling of magnetization (QTM) is found to exhibit negative correlation with the structural-related value Stun corresponding to the axial coordination bond angles.