Ferro-/antiferromagnetic interactions in two one-dimensional Cu(II) complexes: Syntheses, crystal structures and magnetic studies

The synthesis, structural characterization, and magnetic properties of two new Cu(II) coordination polymers with formula {[Cu(2-nica)(H2O)2]∙H2O}n (1) and [Cu(6-nica)(H2O)2]n (2) (where 2-H2nica = 2-hydroxynicotinic acid and 6-H2nica = 6-hydroxynicotinic acid) are reported. 1 exhibits 1D chain structure formed by the sequence of [Cu(II)single bondOsingle bondCu(II)]. For 2, nitrogen atoms and μ1,3-COO carboxylic groups of 6-nica2 − bridge Cu(II) ions forming an infinite chain structure. The ESR spectra, as well as the variable temperature magnetic susceptibilities were analyzed, which suggests ferromagnetic coupling in 1 and antiferromagnetic coupling in 2, respectively.