Abstract
Coordination compounds of the Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions with the thiosemicarbazones of aceto-phenone (HAPT), p-aminoacetophenone (HpAAPT) and p-acetylaceto-phenone (HpAcAPT) were synthesized. Their structures have been assigned based on elemental analyses, molar conductivity, magnetic susceptibilities (at ∼25°C) and spectral (IR, NMR, reflectance) studies. The IR spectra show that the ligands act in a monoanionic bidentate or a neutral monodentate fashion depending on the metal salt used and the medium of the reaction. Tetrahedral structures for the Co(II) complexes and square-planar structures for both Ni(II) and Cu(II) complexes are proposed on the basis of magnetic and spectral evidence. The complex formation in solution was investigated potentiometrically and spectrophotometrically. The electrical conductivities of HAPT and HpAcAPT as well as some of their metal complexes are measured at different temperatures. The ΔE values are calculated and agree well with those reported for semiconductors.