A novel two-dimensional (4,4) network based on dinuclear cadmium secondary building units: poly[(μ5-benzene-1,4-diacetato)[μ2-1,4-bis(1,2,4-triazol-1-yl)butane]cadmium(II)].

In the title mixed-ligand metal-organic polymeric compound, [Cd(C(10)H(8)O(4))(C(8)H(12)N(6))](n) or [Cd(PBEA)(BTB)](n) [H(2)PBEA is benzene-1,4-diacetic acid and BTB is 1,4-bis(1,2,4-triazol-1-yl)butane], the asymmetric unit contains one Cd(II) ion, one BTB molecule and one PBEA(2-) anion. The Cd(II) ion is in a slightly distorted pentagonal-bipyramidal geometry, coordinated by five carboxylate O atoms from three distinct PBEA(2-) anions and by two BTB N atoms. There are two coordination patterns for the carboxylate groups of the PBEA(2-) ligand, one being a μ(1)-η(1):η(1) chelating mode and the other a μ(2)-η(2):η(1) bridging mode, while the BTB molecule shows a trans-trans-trans conformation. The crystal structure is constructed from the secondary building unit (SBU) [Cd(2)(CO(2))(4)N(2)O(2)], in which the two metal centres are held together by two PBEA(2-) linkers. The SBU is connected by BTB and PBEA(2-) bridges to form a two-dimensional grid-like (4,4) layer with meshes of dimensions 14.69 × 11.28 Å.