Structural and magnetic studies on a new mixed-valence Cu(I)-Cu(II) octanuclear cluster with a dithiocarbarnate derivative

A new mixed-valence Cu(I)-Cu(II) octanuclear cluster, [(CuCuII)-Cu-I (n-Pr(2)dtc)Cl-2](2)[Cu-2(II)(n-Pr(2)dtc)(2)Cl-2](2) (1) (n-Pr(2)dtc(-) = di-n-propyldithiocarbamate) with a dithiocarbamate derivative has been synthesized and structurally characterized. Complex I consists of a mixed-valence Cu(I)-Cu(II) tetranuclear unit and two chloride-bridged Cu(II) dinuclear units. The octanuclear cluster forms an infinite one-dimensional assembly by weak Cu center dot center dot center dot Cl and Cu center dot center dot center dot S coordination bonds between the chloride bridged dinuclear units. The magnetic study indicates the existence of a strong antiferromagnetic interaction (J = -35.6 cm(-1)) between the copper ions of the chloride-bridged Cu(II) dinuclear unit, Cu-2(II) (n-Pr(2)dtc)(2)Cl-2. (C) 2006 Elsevier Ltd. All rights reserved.