Two nickel(II), and zinc(II) complexes [ML2](ClO4)2 of N-(2-propanamide)-2-picolylamine , L, derived from the condensation reaction of 2-picolylamine with acrylamide were synthesized. The prepared complexes were characterized by elemental analyses, ultraviolet-visible, infrared, 1-H-NMR spectroscopy techniques, and conductivity measurements. The ligand behaves like an NNO donor set, forming octahedral geometries with both Ni(II) and Zn(II) complexes. The nickel complex is halochromic. pH effects on the visible absorption spectra of the nickel complex were investigated in the range of 2-13. Its color change was due to the protonation and deprotonation of labile moieties of the ligand at room temperature. The complex displayed reversible thermochromism in solvents of DMSO and DMF attributed to the dissociation of hemilabile amide moieties from the metal center and substituted by solvent molecules. For the purpose of assigning experimental data to the ligands and complexes, a density function theory calculation on the level of B3LYP/LanL2DZ was performed.
