Exploring the Dual Realm of Solvent-Responsive Structural Transformations and Semiconducting Properties of Six 1D Coordination Polymers

Six coordination polymers of Zn(II)/Cd(II)/Co(II) have been synthesized using the same N,N-donor ligand, namely, N′-(1-(pyridine-3-yl)ethylidene) isonicotinohydrazide (3-pei) and two aromatic dicarboxylates, namely, terephthalate (tp2–) and tetrabromo-terephthalate (tbtp2–). The single-crystal structural analysis reveals a one-dimensional framework interconnected by both sides of the dicarboxylyate linker. Notably, the presence of coordinated water in all compounds prompted an investigation into solvent-dependent structural transformations. The systematic exploration of structural transformations using PXRD confirmed solvent-dependent structural variations. Furthermore, band gap calculations from UV–vis data motivated for an examination of the conductive properties of all compounds. The conductivity study indicates that compared to Zn and Cd complexes, the Co-based complexes (compounds 3 and 6) exhibit higher conductance values of 5.76 × 10–4 and 1.33 × 10–3 Sm–1, respectively, which may be applicable for semiconducting materials. The superior conductance of Co compounds and the solvent-dependent structural transformations of all six compounds are explained by correlating with their respective structures.