MIXED-LIGAND LANTHANIDE COMPLEXES .10. INTERACTION OF TRIVALENT LANTHANIDES WITH 1,10-PHENANTHROLINE AND THIOCYANATE IN ALCOHOL

The interaction of trivalent lanthanide thiocyanates and phen in ethan ol results in the formation of the complexes of the type [Ln(phen)(3)( SCN)(3)], where Ln = La, Pr, Nd, Sm and Eu; and [Ln(phen)(3) (SCN)(3)( H2O)], where Ln = Dy, Ho, Er and Yb. The complexes have been character ized by elemental analyses, molar conductance, IR spectra and thermal analyses. The complexes behave as non-electrolytes in methanol. TGA sh owed the presence of coordinated water in the case of the heavier lant hanides making them ten-coordinate. The NMR spectra of the complexes o f La, Pr, Nd, Sm, Eu and Yb have been studied in DMSO-d(6) and pyridin e-d(5). The complexes do not dissociate in DMSO and retain their coord ination number. The chemical shift ratios are constant for different p hen protons which indicates dipolar nature of the shift. Pyridine coor dinates without displacing any ligand and increases the coordination n umber of the lighter lanthanides from nine to ten. (C) 1997 Elsevier S cience Ltd.