Substituent effect on the magnetic properties of copper coordination polymers with dithiooxamide and N,N′-bis-(hydroxyethyl)dithiooxamide

The magnetic properties of copper coordination polymers with dithiooxamide [H(2)dtoaCu] and its substituent N,N'-bis-(hydroxyethyl)dithiooxamide [(HOC2H4)(2)dtoaCu] have been investigated. They indicate different temperature dependence, which was analyzed by Bleaney-Bowers equation. The estimated J values of H2dtoaCu and (HOC2H4)(2)dtoaCu are -861 and -594 K, respectively. The large negative J values are derived from intradimer antiferromagnetic coupling through the ligands. The absolute J value of H(2)dtoaCu is larger than that of (HOC2H4)(2)dtoaCu, which is considered to be due to the difference of the superexchange interaction between Cu(II) ions via ligands. The electronic structure of the coordination polymer is supposed to depend on the substituent groups. (C) 2002 Elsevier Science B.V. All rights reserved.