Coordination polymers, 1. Magnetic, spectral, and thermal properties of coordination polymers derived from terephthalaldehyde bis(S‐benzyldithiocarbazate)

Abstract

AbstractNew Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) coordination polymers of Schiff base ligand derived from terephthalaldehyde and S‐benzyldithiocarbazate have been synthesized in DMF media. The coordination polymers have been characterized by their elemental analysis, magnetic susceptibility, and by electronic and infrared spectral measurements.The thermal stability of each polymer was found out by thermogravimetric analysis. The thermal stability of coordination polymers obtained from thermograms has the following order: \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm Zn} \simeq {\rm Fe} > {\rm Co} > {\rm Ni} > {\rm Min} \simeq {\rm Cu}$\end{document} Mn(II), Fe(II), Co(II), and Ni(II) coordination polymers are of a six‐coordinated octahedral structure while Cu(II) and Zn(II) coordination polymers are found to be four‐coordinated square planar and tetrahedral structure, respectively. The ligand‐field and nephelauxetic parameters have been determined from the spectra, using ligand‐field theory of spin‐allowed transitions which are found consistent with six‐coordinate structure for Mn(II), Fe(II), Co(II), and Ni(II) coordination polymers. Elemental analyses indicates a ligand: metal ratio of 1 : 1 in all the coordination polymers and the association of water molecules with central metal atom in case of Mn(II), Fe(II), Co(II), and Ni(II) coordination polymers.