Electronic, structural, and optical properties of host materials for inorganic phosphors

A family of large gap insulators used as host materials for inorganic phosphors (La2O3, La2O2S, Y2O3, Y2O2S, La2TeO6, and Y2TeO6) have been studied by first-principles DFT based calculations. We have determined electronic, structural, and optical properties for all these compounds both at the LDA and GGA levels obtaining, in general, a good agreement with available experimental data and previous theoretical studies. The electronic structure for the M2TeO6 phases, addressed in this work for the first time, reveals some significant differences with respect to the other compounds, especially in the region of the lower conduction band, where the appearance of a group of four isolated oxygen/tellurium based bands below the main part of the La (Y) centered conduction band is predicted to lead to significant changes in the optical properties of the two tellurium containing compounds with respect to the rest of compounds in the series. (C) 2011 Elsevier B.V. All rights reserved.