Synthesis and crystal structure of a two-dimensional Co(II) coordination polymer: poly[(μ(3)-3-carb­oxy­benzoato)[μ(2)-5-(pyridin-4-yl)-1H,2′H-3,3′-bi[1,2,4-triazole]]cobalt(II)]

In the title compound, [Co(C(8)H(5)O(4))(C(9)H(6)N(7))](n), the divalent Co(II) atom is six-coordinated to three N atoms from two symmetrical 5-(pyridin-4-yl)-1H,2′H-3,3′-bi[1,2,4-triazole] (H(2)pyttz) ligands and three O atoms from three symmetrical 3-carb­oxy­benzoate (Hbdic) ligands, leading to a distorted {CoN(3)O(3)} octa­hedral coordination environment. Two Co(II) cations are linked by four bridging carboxyl­ate groups to generate a dinuclear [Co(2)(CO(2))(4)] unit. The dinuclear units are further connected into a chain along [010] via the Hbdic ligands. The other infinite chain, along [100], is formed through the H(2)pyttz ligands. Finally, the two kinds of chains are cross-linked, by sharing the Co(II) cations, into a two-dimensional network. In the crystal, adjacent layers are further linked by O—H⋯N hydrogen bonds into a three-dimensional framework.