Poly[[di-mu-aqua-tetraaquadi-mu-hydroxido-bis(mu3-3-nitrophthalato)tricopper(II)] dihydrate].

The novel title complex, {[Cu(3)(C(8)H(3)NO(6))(2)(OH)(2)(H(2)O)(6)].2H(2)O}(n), has a one-dimensional polymeric double chain structure where the three Cu atoms are linked by mu(2)-OH and mu(2)-H(2)O groups, and these trinuclear centres are bridged by two 3-nitrophthalate ligands. The asymmetric unit contains one and a half crystallographically independent Cu atoms (one lying on a centre of inversion), both coordinated by six O atoms and exhibiting distorted octahedral coordination geometries, but with different coordination environments. Each 3-nitrophthalate ligand connects to three Cu atoms through two O atoms of one carboxylate group and one O atom of the nitro group. The remaining carboxylate group is free and is involved in intrachain hydrogen bonds, reinforcing the chain linkage.