Macrocyclic Hexagonal Bipyramidal Dy(III)-Based Single-Molecule Magnets with a <i>D</i><sub>6<i>h</i></sub> Symmetry
Shuwen Jia, Xinrui Zhu, Bing Yin, Yubao Dong, Ao Sun, Dongfeng Li
Abstract
The design and synthesis of air-stable single-molecule magnets (SMMs) with large effective barriers of magnetic reversal and remarkably slow relaxation times are challenging. The design and synthesis of air-stable complexes with large effective magnetic reversal barriers and remarkably slow relaxation times are challenging in the field of SMMs. Herein, we present an air-stable hexagonal bipyramid [Dy III (bpyN4)(Ph 3 SiO) 2 ](BPh 4 ) ( 1 ) (bpyN4 = neutral hexaaza macrocyclic Schiff base ligand derived of 6,6′-diformyl-2,2′-bipyridyl and triethylenetetramine). The magnetic data demonstrate that the complex shows zero-field SMM behavior with magnetic hysteresis loops up to 13 K and an effective barrier of 584 K for 1 . The experimental effective barrier is close to the energy of the first excited Kramers doublet ( E KD1 ) obtained from ab initio calculations.