The Nephelauxetic Effect in Praseodymium(III) and Neodymium(III) Complexes

Abstract

measuredin an aqueous alkaline solution with an excess of ligands. The experimental data least-squares method on the assumption that the energy separation between _J-levels of the 4fn-It has been known that the radial integrals of the valence orbitals of a metal ion decrease when the free metal ion combines with ligands to form a metal complex.1) This phenomenon is called the nephelauxetic effect, which means the expansion of electron clouds; it may be regarded as a measure of the covalency of coordination bands.1) Although the nephelauxetic effect has been extensively investigated in d-transition metal complexes, the study of f-transition metal complexes has been rather limited because of the theoretical and experimental difficulties.which are attributed to the electronic transitions within the 4fn-configuration (n=2-12), are shifted when the environment of the ion is changed. This is undoubtedly an indication of a change in the ions the spin-orbit interaction can not be neglected and the radial integrals should be treated by an intermediate coupling scheme.3) The separation between J-levels of the 4fn-configuration may be expressed in terms of the radial integrals (f)4) and the spin-orbit coupling parameter.

Optical properties of Nd(DBM)3Phen in MMA and PMMA

“…When the free metal ion combines with ligands to form a metal complex, the radial integrals of the valence orbits of a metal ion will be decreased [22,23]. This phenomenon is known as the nephelauxetic effect, which means the expansion of electron clouds.…”

Electronic spectral study of amino-acid complexes of Nd(III)

“…Theoretically the oscillator strength, P,,,,, of the induced-dipole transition of energy v (cm-I) in accordance with Judd-Ofelt relation [ 1 ] can be expressed as: [3] …”