Some Rare Earth Chelates of N-thioacetyl-N-phenylhydroxylamine

Abstract

The stability constants of La(III), Pr(III), Nd(III), Sm(III), Gd(III) and Y(III) with N-thioacetyl-N-phenylhydroxylamine have been determined potentiometrically in 50% dioxane aqueous medium at 0.1 M ionic strength at 30ºC. The method of Bjerrum-Calvin has been employed to find the value of formation constants, Block McIntyre and pointwise calculation methods have been applied for the calculation of stepwise and overall stability constants of rare-earth ions. The stability sequence for 1 : 1 (metal : ligand) complexes is found to be:

                              Sm> Y>Gd>Nd>Pr>La