Studying the absorption difference and comparative 4ƒ-4ƒ transition spectra of Nd(III) with hexafluoroacetylacetone[C5H2O2F6] and their complexes with o-phenanthroline and bipyridyl using comparative absorption spectroscopy involving 4ƒ-4ƒ transitions in various solvents like methanol acetonitrile and dimethylformamide, the change in coordination sphere in various solvent medium is observed. The 4ƒ-4ƒ transition spectra yield sharp bands which were analyzed individually by Gaussian curve analysis, the energy interaction parameters (F2,F4,F6&,E1, E2, E3)Lande spin orbit coupling (ξ4f), nephelauxetic ratio (β), bonding parameter (b1/2), percent covalency (δ), oscillator strength (P) were calculated and Judd Oflet intensity parameters have been computed on computer using partial multiple regression analysis.
