On the charge factors of the simple overlap model for the ligand field in lanthanide coordination compounds

In this Letter, we propose a semi-empirical procedure through which the cha rge factors, appearing in the simple overlap model (SOM) for the ligand fie ld in lanthanide compounds, can be obtained. The idea is based on the conce pt of bond valence and bond strength introduced by Pauling in the 1920's. T he charge factors thus obtained are used in the calculation of the so-calle d ligand held parameters, B-q(k)'s, and, subsequently, in the prediction of the Stark levels of the F-7(J) manifolds (J = 1,2, 3 and 4) of the Eu3+ io n in coordination compounds with mixed ligands. Comparison with experiment shows that the results are quite satisfactory. (C) 2000 Elsevier Science B. V. All rights reserved.