Structure and magnetic properties of a 3d–4f CoIII2DyIII4 cluster

Abstract

Structural determination and magnetic studies of a 3d–4f heterometallic hexanuclear [CoIII2DyIII4(μ3-OH)2(salpa)4(NO3)4(OAc)4(H2O)2] (1) cluster, where H2salpa=N-(2-hydroxybenzyl)-3-amino-1-propanol, are reported. Single-crystal X-ray diffraction studies reveal that the cluster contains a defect-dicubane central core composed of four DyIII ions, which are supported by two oxygen atoms from the acetate groups, two alkoxo groups and two μ3-OH groups, which are displaced above and below the Dy4 plane. Moreover, the remaining CoIII ions are linked to the defect-dicubane core through two alkoxo groups and two phenoxido groups. Because of the presence of diamagnetic CoIII ions, the magnetic properties of complex 1 can be attributed to the presence of the four DyIII ions. Variable temperature direct current (dc) magnetic susceptibility measurements reveal spin–orbital coupling and/or antiferromagnetic interactions between the DyIII ions. Alternating current (ac) magnetic susceptibility measurements indicate that complex 1 exhibits slow magnetization relaxations.