Phenomenological spin-correlated crystal-field analyses of energy levels in Ln 3+:LaCl 3 systems

Abstract

The best energy level data available in the literature for the Ln 3+:LaCl 3 systems are analyzed in terms of an electronic hamiltonian that includes isotropic (free-ion) and crystal-field interaction parameters for C 3 h site symmetry. The crystal-field hamiltonian is defined to include spin-correlated crystal-field (SCCF) interaction terms, and analyses are carried out with and without consideration of these SCCF terms. The analyses reported here yield improved calculated- vs.-experimental energy level fits (compared to fits reported previously in the literature). For example, for Ho 3+:LaCl 3, the value of sigma is improved from 7.8 to 4.9 cm −1 for 168 crystal-field levels. In each case, inclusion of the SCCF terms improves the calculated- vs.-experimental energy level data fits. Ratios of the SCCF vs. one-electron crystal-field parameters are reported and compared for each system.