Selective H2PO4− anion sensing by two neutral Zn2+ complexes and combined theoretical and experimental studies of their structural and spectral properties

Two mononuclear Zn2+ complexes containing O, N, N coordinating ligands derived from thiazole and a substituted phenol moiety have been synthesized. The X-ray structure of one complex is reported as a representative case. The mechanism of metal ion interaction with the ligands has been confirmed by emission and absorbance titrations. The sensing properties of the synthesized complexes towards the phosphate ion are studied. Full density functional theory (DFT) and time-dependent density functional theory (TDDFT) have been investigated to get a better insight into the geometry, electronic structure and optical properties of this system.