New [2x2] cyclic framework that induces distortions from square planar to tetrahedral around the copper(II) centers

A new tetracopper(II) complex [CU4(bsbd)(4)] (bsbd = bis(N-salicylidene)benzene-1,4-diamine) has been prepared and structurally characterized. The complex constructs a [2 x 2] cyclic coordination framework, which inhibits formation of square planar copper(II) centers, and induces distortion to a tetrahedral structure. The effects of the distortions on the absorption spectra are characterized. (c) 2007 Elsevier B.V. All rights reserved.