title: Two pseudo-polymorphic copper-benzene-1,2,4,5-tetracarboxylate complexes.
abstract: Two pseudo-polymorphic polymers, poly[ethylenediammonium [[aquacopper(II)]-micro(4)-benzene-1,2,4,5-tetracarboxylato] dihydrate], [(C(2)H(10)N(2))[Cu(C(10)H(2)O(8))(H(2)O)].2H(2)O](n), (I), and poly[ethylenediammonium [copper(II)-micro(4)-benzene-1,2,4,5-tetracarboxylato] 2.5-hydrate], [(C(2)H(10)N(2))[Cu(C(10)H(2)O(8))].2.5H(2)O](n), (II), contain two-dimensional anionic layers, ethylenediammonium (H(2)en) cations acting as counter-ions and free water molecules. Although the topological structures of the two anionic layers are homologous, the coordination environments of the Cu(II) centres are different. In (I), the Cu(II) centre, sitting on a general position, has a square-pyramidal environment. The two independent benzene-1,2,4,5-tetracarboxylate (btc) anions rest on centres of inversion. The Cu(II) cation in (II) is located on a twofold axis in a square-planar coordination. The H(2)en cation is on an inversion centre and the btc ligand is split by a mirror plane. Extensive hydrogen-bonding interactions between the complexes, H(2)en cations and water molecules lead to the formation of three-dimensional supramolecular structures.
authors.affiliation: Department of Chemistry, Fuzhou University, Fuzhou, Fujian, People's Republic of China.
authors.forename: Jian Hai
authors.initials: JH
authors.lastname: Luo
authors.forename: Chang Cang
authors.initials: CC
authors.lastname: Huang
authors.forename: Xi He
authors.initials: XH
authors.lastname: Huang
authors.forename: Xiao Juan
authors.initials: XJ
authors.lastname: Chen