STRUCTURE OF COPPER(II) CHLORANILATE TRIHYDRATE

Copper(II) 3,6-dichloro-2,5-dihydroxy-1,4-benzoquinone trihydrate, Cu(C6Cl2O4).3H2O, M(r) = 324.56, triclinic, P1BAR, a = 7.040 (4), b = 7.962 (4), c = 9.364 (5) angstrom, alpha = 84.58 (3), beta = 89.25 (3), gamma = 76.53 (3)-degrees, V = 508.1 (5) angstrom 3, Z = 2, D(x) = 2.12 Mg m-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 2.7 mm-1, F(000) = 322, room temperature, R = 0.048 for 1465 unique reflections having \F\ > 3-sigma(\F\). The Cu atoms are coordinated in a moderately distorted octahedral arrangement by four ligand atoms and two water molecules. There are three significantly different Cu-O distances: 1.966 (4) and 1.965 (5) angstrom to the two 'phenolic' O atoms, 2.252 (4) and 2.265 (4) angstrom to the two quinoid O atoms and to the two water-molecule O atoms 1.996 (4) and 2.015 (5) angstrom. There are layers of linear coplanar chains of Cu atoms bridged by chloranilate dianions. Between the chains there is one 'free' water molecule per Cu atom.