title: catena-Poly[[bis-(3,5-dicarboxy-benzo-ato)cobalt(II)]-μ-4,4'-bipyridine].
abstract: In the title compound, [Co(C(9)H(5)O(6))(2)(C(10)H(8)N(2))](n), the asymmetric unit consists of one Co(2+) ion with site symmetry 2, one mono-deprotonated 1,3,5-benzene-tricarboxylic acid anion and one-half of a 4,4'-bipyridine (4,4'-bipy) mol-ecule, in which two N and two C atoms have site symmetry 2. In the crystal structure, the Co(2+) centre is coordinated by four O atoms from two bidentate carboxyl-ate groups of two anions and two N atoms of two 4,4'-bipy mol-ecules, resulting in infinite chains propagating in [010]. The cobalt coordination is distorted trans-CoO(4)N(2) octa-hedral and inter-chain O-H⋯O hydrogen bonds complete the structure.
authors.forename: Chun-Sheng
authors.initials: CS
authors.lastname: Ling
authors.forename: Qiu-Xia
authors.initials: QX
authors.lastname: Han