Crystal field study of Chromium(III) ions doped antimony phosphate glass: Fano’s antiresonnance and Neuhauser models

Abstract

The absorption spectrum of antimony phosphate glass doped with Cr³⁺ is characterized by the presence of features on the ⁴T_2g(⁴F) absorption band. These features result from the interaction of the ²E_g(²G) and ²T_1g(²G) sharp levels with the vibrationally broadened ⁴T_2g(⁴F) quasi-continuum via spin-orbit coupling called interference dips. We have analyzed this phenomenon through two models: Fano’s antiresonance and Neuhauser models. This analysis permits us to determine the electronic structure of the chromium ion Cr³⁺ based on the crystal field theory. As a result, Racah and crystal-field parameters have been reliably obtained. A good agreement between the theoretical and the experimental energy levels are obtained.