Magnetic dynamics of two salen type Dy2 complexes modulated by coordination geometry†
Abstract
Two salen type dinuclear dysprosium complexes, namely [Dy(H2L) (NO3)3]2·CH2Cl2·CH3OH·H2O (1) and [Dy(H2L1)2(NO3)3]2·2CH2Cl2·2CH3OH (2) [H2L = N,N′-(1,3-propylene)bis(3-methoxysalicylideneimine) and H2L1 = N,N′-(1,3-propylene)bis(salicylideneimine)], were isolated from the reactions of Dy(NO3)3·6H2O with two different but similar salen type ligands (H2L and H2L1), respectively. X-ray crystallographic analyses revealed that two crystallographically equivalent Dy(III) ions for 1 and two crystallographically non-equivalent Dy(III) ions for 2 were both bridged by two ligands displaying broken hula hoop-like and hula hoop-like coordination geometries for complexes 1 and 2, respectively, which resulted in the distinct magnetic properties that complex 2 exhibited with relatively higher energy barriers under a 2 kOe dc field.