PREPARATION, CHARACTERIZATION AND SPECTROSCOPY OF THE EUROPIUM DIPHENYLPHOSPHINATE COMPLEX

The purpose of this work is to study the preparation and spectroscopic behavior of the europium diphenylphosphinate complex - Eu(DPP)(3). El emental and thermogravimetric analysis, powder X-ray diffractometry, a nd infrared spectroscopy were applied to characterize the formula of t he final product and the sixfold coordination of the Eu3+ ion. Excitat ion and emission spectra have been recorded at liquid nitrogen and roo m temperatures. The D-5(0) --> F-7(2) transition intensity decreases w hen T decreases in comparison to the D-5(0) --> F-7(1) transition inte nsity. Molecular mechanic calculations were developed in order to obta in the spatial coordinates of the Eu3+ and ligand ions. The simple ove rlap model was used to calculate the total splitting of the D-5(0) --> F-7(1) transition, D-5(0) --> F-7(0)/D-5(0) --> F-7(2) intensity rati o and the intensity parameters, Omega lambda (lambda = 2 and 4). Good agreements between theoretical predictions and experimental results ha ve been obtained with g = 2/3 as the effective charge and alpha = 0.8 x 10(-24) cm(3) as the isotropic polarizability of the oxygen. (C) 199 8 Elsevier Science S.A.