SYNTHESIS, MAGNETIC, SPECTRAL AND THERMAL STUDIES OF SOME LANTHANIDE NITRATE AND ISOTHIOCYANATE COMPLEXES WITH 4[N-(4-DIMETHYLAMINOBENZYLIDINE)AMINO]ANTIPYRINE

A new series of complexes of lanthanide(III) nitrate and isothiocynates with 4[N-(4-dimethylaminobenzylidene)amino]antipyrine (DABAAP) having the general formula [Ln(DABAAP)(2)(NO3)(3)] (where Ln = La, Pr, Nd, Sm, Gd, Tb or Dy) and [Ln (DABAAP)(n)(NCS)(3)] (n = 2, Ln = La or Pr; n = 3, Ln = Nd, Sm, Gd, Tb, or Dy) have been synthesized and their i.r. and electronic spectra obtained. In these complexes DABAAP acts as a bidentate ligand coordinating through the carbonyl oxygen and azomethine nitrogen atoms. The nitrate ion acts as a bidentate ligand and the isothiocyanate ion is N-coordinating with the lanthanide ion. The probable coordination number of the Ln(3+) ion varies among seven, nine and ten. The thermal stability of the complexes have also been studied through t.g. analyses.