{[Cu(mal)(bipy)]·2H 2O} n: a new one-dimensional ladder-like copper(II) complex based on the mixed N- and O-donor ligands with intrachain ferromagnetic interactions

Abstract

The novel ladder-like one-dimensional copper(II) complex of formula {[Cu(mal)(bipy)]·2H 2O} n (mal, the maleic acid dianion, bipy, 2,2′-bipyridine) has been synthesized using the maleic acid dianion and 2,2′-bipy as the mixed ligands. The single-crystal X-ray diffraction reveals that the two carboxylate groups of the maleic acid dianion exhibit two different coordination modes in the complex. One acts as a bridge in the syn–anti conformation, while the other exhibits the monodentate coordination mode. The magnetic properties of the complex have been studied by susceptibility measurements as a function of the temperature and successfully analyzed in terms of the isotropic spin Hamiltonian for one-dimensional infinite system H=−2 J∑ S i S i+1 . Magnetic calculations showed the presence of ferromagnetic exchange interactions between the copper(II) ions within the chain with J=2.41 cm −1.