Spectroscopy of Mn4+ in Double Perovskites, La2LiSbO6 and La2MgTiO6: Deep Red Photon Generators for Agriculture LEDs

摘要

The optical properties of Mn4+ (3d(3)) in the double perovskites, La2LiSbO6 and La2MgTiO6, are investigated. The Mn4+ energy levels are calculated using the exchange charge model of crystal-field theory and compared with the experimental spectroscopic data. A comparative study of the optical properties of Mn4+ in the perovskite structure shows that energy of the E-2(g) - (4)A(2g) emission transition is determined by octahedral site distortion. The greater is the site distortion, the lower is the Mn-O covalent interaction and the higher is the energy of the E-2(g) - (4)A(2g) emission transition. The work provides guidelines for the development of deep red emitting phosphors for agricultural (horticultural) applications. (c) The Author(s) 2017. Published by ECS. All rights reserved.