Studies on Lanthanide (III) Complexes with N-Substituted Thioureas

Abstract

Lanthanide (III) complexes of N-thioureas of the type [MX_3–mnL] X_m2H₂O [M = Sm(III), Eu(III), Dy(III) and Y(III); X = NO^–₃, Cl^–; L=m-chlorophenyl thiourea (m-Clptu), p-chlorophenyl thiourea (p-Clptu), m-hydroxy phenyl thiourea (m-OHptu); m = 0, 1 and n = 3, 4] have been synthesized and characterized by elemental analysis, conductivity, magnetic moment, IR and visible spectra and thermal studies. All complexes are nonelectrolytes except [Sm(NO₃)₂(m-OHptu)₄] NO₃·2H₂O which is 1 : 1 electrolyte. Barring Y(III) complexes, all others exhibit paramagnetism. While IR spectral data unequivocally suggest S bonding of ligands, results from visible spectra evaluate the extent of covalency.