A tetradendate Schiff-base ligand, N,N'-bis-(4-chlorobenzylidene)-1,2-bis(2-aminophenylthio)ethane, L, and its copper(I) coordination polymers, [Cu-2(mu-I)(2)-mu-L](n)center dot 2n(CH3CN), LCuIS, and [Cu-2(mu-Cl)(2)-mu-L](n), were prepared. The products were characterized via their analytical and spectral properties. The crystal structures of the ligand molecule, L, and the complex, LCuIS, were determined by single-crystal X-ray diffraction methods. In both the free molecule and the complex, L adopts an anti, staggered, extended conformation. In LCuIS, prepared from L and CuI in acetonitrile, each Cu atom has a distorted tetrahedral coordination sphere composed of a nitrogen atom and a sulfur atom from L and two iodine ligands. LCuIS is a sheet polymer, formed from coordination polymer chains containing the dimetal clusters Cu-2(mu-I)(2); the chains are crosslinked through pi center dot center dot center dot pi interactions of phenyl rings. (C) 2011 Elsevier B.V. All rights reserved.