LAUSR

Abstract The low temperature spectroscopic properties of Mn4+ (3d3) in the orthorhombic perovskite, LaInO3, is examined in this work. The exchange charge model of crystal-field theory is used to calculate the Mn4+ energy levels. The spectra can be fitted by the parameters Dq = 1776 cm−1, B = 700 cm−1 and C = 3189 cm−1, with C/B = 4.5. Discussions pertaining to the low luminescence efficiency of LaInO3:Mn4+ are presented. A comparative study of the variations in the energy of the 2Eg→4A2g emission transition in a series of materials with the perovskite structure is presented. The data suggest a relationship between the energy of the 2Eg→4A2g emission transition and the deviation of the octahedral O-Mn-O bond angle from the ideal 90°. It is concluded that the angular distortion is not large enough to support the development of high luminosity Mn4+ activated phosphors in the ABO3 perovskite family of materials.