Ferromagnetic interactions in copper(II) and nickel(II) coordination polymers containing nitronyl nitroxide radical and terephthalate

摘要

Two new complexes [Cu(NITmPy)(2)(tp)] 1 and [Ni(NITmPy)(2)(tp)(H2O)(2)] 2 (NITmPy=2-(3'-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and tp=terephthalato dianion) were synthesized and structurally and magnetically characterized. The structure of 1 is a neutral infinite chain where Cu(NITmPy)(2) units are linked by terephthalate ligands. In complex 2, the 1-D chains of Ni(NITmPy)(2) (H2O)(2) units connected by tp develop into 2-D network via hydrogen bond interactions. The magnetic properties of 1 and 2 have been investigated in the temperature range 2-300 K. Both complexes exhibit ferromagnetic coupling and antiferromagnetic interactions dominate at low temperature. The magnetic behavior is discussed based on their structures. (C) 2003 Elsevier B.V. All rights reserved. [References: 36]