Structure and magnetic properties of a novel heterospin 1-D chain complex containing both Cu(II) and nitroxide radicals as spin branches

A novel heterospin one-dimensional (1-D) chain complex containing both Cu(II) and nitroxide radical ligands, {[Cu(tcph)(H2O)(4)][Cu(tcph)(NIT3Py)(2)]center dot 2H(2)O} (n) (1) (H(2)tcph = tetrachloro-phthalic acid, NIT3Py = 2-(3'-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), has been synthesized and structurally characterized. The structure consists of neutral chains of copper(II) ions bridged by tcph and coordinated alternatively by nitroxide radicals as spin branches and solvated water as co-ligand. The magnetic data were fitted using an approximate theoretical model based on population analysis to obtain the coupling parameter values of J (Cu2-Rad) = 22.4 cm(-1) and J'(Cu1-Cu2) = -2.4 cm(-1), indicating the intramolecular ferromagnetic interaction between Cu(II) and NIT3Py and weak antiferromagnetic interaction between Cu1 and Cu2 linked by tcph.