Optical Spectroscopy and Crystal Field Studies of the Mn4+ Ion (3d3) in the Double Perovskite NaLaMgTeO6

The spectroscopic properties of the Mn ion (3d ) in the double perovskite NaLaMgTeO are reported in this work. Evidence is presented for the occupation by the Mn ion of both the six coordinated Mg and Te sites in the host structure. The Mn energy levels are calculated using the exchange charge model of crystal field theory for both occupied sites. The results of our calculations yield the crystal field splitting and Racah parameters of Dq = 2008 cm , B = 790 cm , C =2881 cm , with C/B=3:65 (Mg site) and Dq=2008 cm , B=790 cm ,C =2949 cm , with C/B = 3:73 (Te site). A cross-cutting comparative study of the variations in the crystal field splitting and the Racah parameters of the six-coordinated Mn ion in a series of materials with the perovskite structure are presented.