Macrocyclic Hexagonal Bipyramidal Dy(III)-Based Single-Molecule Magnets with a D (6h ) Symmetry

An air-stable Dy-III complexwith a hexagonalbipyramid D (6h) symmetry derived of a neutralhexaaza macrocyclic Schiff base ligand shows zero-field single-moleculemagnet behavior with an open magnetic hysteresis loop up to 13 K andthe effective barrier of 584 K. Thedesign and synthesis of air-stable single-molecule magnets(SMMs) with large effective barriers of magnetic reversal and remarkablyslow relaxation times are challenging. The design and synthesis ofair-stable complexes with large effective magnetic reversal barriersand remarkably slow relaxation times are challenging in the fieldof SMMs. Herein, we present an air-stable hexagonal bipyramid [Dy-III(bpyN4)(Ph3SiO)(2)](BPh4)(1) (bpyN4 = neutral hexaaza macrocyclic Schiff baseligand derived of 6,6 & PRIME;-diformyl-2,2 & PRIME;-bipyridyl and triethylenetetramine).The magnetic data demonstrate that the complex shows zero-field SMMbehavior with magnetic hysteresis loops up to 13 K and an effectivebarrier of 584 K for 1. The experimental effective barrieris close to the energy of the first excited Kramers doublet (E (KD1)) obtained from ab initio calculations.

Automated summary

This article describes an air-stable Dy-III complex with a hexagonal bipyramid D (6h) symmetry derived from a neutral hexaaza macrocyclic Schiff base ligand. The complex exhibits zero-field single-molecule magnet behavior with an open magnetic hysteresis loop up to 13 K and an effective barrier of 584 K.