Spectral thermal and X-ray diffraction studies of La(III) and Sm(III) complexes of nitrogen and sulphur donor ligands

Abstract

Some interesting lanthanide metal chelates of nitrogen and sulphur donor ligands, e.g. salicylalidinethiosemicarbazone, 2 - hydroxy - 1 - naphthalidinethiosemicarbazone and 2 - hydroxyacetophenoneiminethiosemicarbazone (TSCH 2 ) have been prepared by 1:1, 2:3 and 1:2 (M:L) molar reactions of tris-(isopropoxyl)lanthanum or samarium under anhydrous conditions. The elemental analysis, molecular weight determinations, conductance measurements and IR, proton magnetic resonance and electronic spectral studies along with magnetic measurements are discussed in relation to the characteristics and proposed structures for these newly synthesized compounds. The thermolytic decomposition of a few chelates has also been studied and the data have been used for evaluating the kinetic parameters along with thermal stabilities. The X-ray powder diffraction patterns of the representative compounds have been used for determining the crystal symmetry of the proposed structures and the cell parameters along with the number of molecules per unit cell.