Taking advantage of a new boron-bridged bicyclic crown ether (EO5-B-EO5−) as the hexagonal planar ligand, a novel dinuclear Dy(III) complex, namely Dy2(EO5-B-EO5)(2,6-dichloro-4-nitro-PhO)4(BPh4) (1), was successfully isolated. Each Dy(III) center adopts a hexagonal bipyramidal coordination geometry, while the intramolecular Dy1···Dy2 distance is 6.2083(3) Å in the Dy2 dimer. This complex shows typical slow magnetic relaxation behavior. Ab initio calculations revealed that the highly anisotropic ground states originate from the pseudolinear O–Dy–O ligand field, while the Ising axes of the two Dy ions are nearly perpendicular to each other, leading to weak antiferromagnetic interaction between the two Dy ions.
Liu et al. (Wed,) studied this question.