Density functional theory calculations of structural, electronic and optical properties of LaPO4:Eu

Monoclinic LaPO4 and LaPO4:Eu have been prepared by the hydrothermal method. The phase composition, UV-Vis absorption spectrum, excitation and emission spectra of as-obtained products were measured. Theoretical calculations of the structural, electronic and optical properties of LaPO4 and LaPO4:Eu were also carried out. The results indicated that the lattice parameters, energy gap and optical properties were in good agreement with the experimental results. The impurity energy levels induced by the 4f states of Eu expanded the absorption edge and decreased the band gap. The charge transfer energy of O(2p)-Eu(4f) calculated was about 4.41 eV, which was close to the value achieved in excitation spectrum (4.5 eV). (C) 2014 Elsevier B.V. All rights reserved.