Elusive Network Topology of a 5-Connected Self-Catenated 3D Coordination Polymer: Featuring Ligand Formation via the In Situ S-S Bond

This article describes the synthesis of a new Zn(II)-based three-dimensional coordination polymer (3D CP) [Zn-2(4,4 '-dsb)(2)(4,4 '-bpy)(3)]<middle dot>(solvent)(x) [H(2)4,4 '-dsb = 4,4 '-disulfanediyldibenzoic acid and 4,4 '-bipyridine (4,4 '-bpy)] (1). Here, the originally used 4-mercaptobenzoic acid (4-mba) undergoes in situ dimerization via the S-S bond to produce H(2)4,4 '-dsb. Fascinatingly, compound 1 exhibits a scarcely reported self-catenated 5-connected underlying net with point symbol {4(2)<middle dot>6(8)}. As far as our knowledge is concerned, this tangled network is the first of this kind among CPs. The calculated highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) band gap computed from density functional theory (DFT) calculation along with well-corroborated experimental values obtained by Tauc's plot reveals the conducting nature of the synthesized material.