Experimental and theoretical investigation of structure-magnetic properties relationships in a new heteroleptic one-dimensional triple bridged azido/acetato/DMSO copper (II) coordination polymer

Abstract

We report the synthesis, structure, and magnetic investigation of a novel one-dimensional copper (II) coordination polymer: formula [Cu(μ1,1N3)(μ1,3OAc)(μ-DMSO)]∞ (1) (OAc=acetate). The connection between neighbouring copper ions arises through a triple bridge involving EO type azide, syn–syn carboxylate and μ-DMSO molecule in apical positions forming an elongated octahedral coordination of copper ions. Magnetic susceptibility measurements show that complex (1) exhibits ferromagnetic intrachain interactions Jchain = +66 cm−1 whereas a metamagnetic behaviour occurs below 2.1 K related with antiferromagnetic inter-chain interactions with a critical field of 600 Oe at 1.8 K. DFT calculations were caried out to rationale the in-chain ferromagnetic interactions between copper ions. We found that the ferromagnetic coupling between copper ions is less sensitive to variation of bond length and/or Cu-N-Cu angle that may be caused by external stimulus such as temperature or pressure.