Absorption spectral study of mixed ligand complexes of some biochemically important polyamine polycarboxylic acids with Nd(III) and Pr(III)

Abstract

Absorption spectroscopy has been used as a tool to understand the coordination of a mixed ligand complexes of neodymium (III) and praseodymium (III) with the polyamino carboxylic acids, viz., nitrilotriacetic acid, 10-(2-hydroxypropyl)-1,4,7-10 tetraazacyclo dodacane 1,4,7-triacetic acid, ethylene diamine-N,N,N',N'-tetraacetic acid, cyclohexylene diamine tetraacetic acid, and diethylene triamine-N,N,N',N'-pentaacetic acid (NTA, HEDTA, EDTA, CDTA and DTPA) in presence of acetyl acetone in aquo-organic medium (DMF/H₂O). The spectral characteristics like oscillator strengths, Tλ, and Judd-Ofelt intensity parameters of the 4f-4f transitions have been evaluated in order to investigate the formation and the type of bonding in lanthanide-ligand complexes in DMF. The values have been computed for energy interaction Slater Condon (Fk'), nephelauxetic effect (β), bonding (b¹/²) and %covalency (δ) parameters.