Synthesis, Crystal Structure and Magnetic Behaviour of Two 1-D Chain Manganese-Nitroxide Complexes Bridged by Isophthalate Anions

Two one-dimensional (1-D) chain manganese-nitroxide complexes {[Mn(NIT4Py)2(ip)(H2O)2]·4H2O}n (1) and [Mn(IM4Py)2(ip)(H2O)2]n (2) (NIT4Py = 2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, IM4Py = 2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl and ip = isophthalate anion) have been synthesized and characterized by elemental analyses, IR spectrum and electronic absorption spectra. Complex 1 was structurally characterized and it crystallizes in neutral 1-D chains where MnII nitroxide units [Mn(NIT4Py)2(H2O)2] are linked by isophthalate anions. The magnetic measurements show that complex 1 exhibits antiferromagnetic couplings, while complex 2 exhibits ferromagnetic interactions between the MnII ion and the nitroxide radicals.