Investigation of the Cr3+ centers in Rb2ZnF4, Rb2CdF4, and Rb2MgF4 fluorine compounds: A semi-empirical analysis

Abstract

The trivalent chromium centers, namely tetragonal (TE) center I and orthorhombic (OR) centers III and IV, have been explored by means of semi-empirical analyses in Rb2MF4 crystals. The local structures for all Cr3+ centers are comprehensively investigated through the zero-field splitting (ZFS) parameters (ZFSPs), which are calculated theoretically and modeled following several modeling approaches. Based on the correlation between the experimental and theoretical ZFSPs, the local structure distortions around the Cr3+ centers are obtained. This study shows that the semi empirical calculations provide a powerful way to determine the local structure in the vicinity of all Cr3+ centers in Rb2MF4 crystals. (C) 2015 Elsevier B.V. All rights reserved.