Photon cascade emission in Pr3+ doped fluorides with CaF2 structure: Application of a model for its prediction

In this work, we predict and measure the optical behaviour of Pr3+ in different binary and ternary fluorides. We use a validated model based on Ligand Field Theory and Density Functional Theory to calculate the multiplet energy levels arising from the ground [Xe]4f(2) and excited [Xe]4f(1)5d(1) electron configurations of Pr3+ in its chemical environment. Moreover, the luminescence spectra of the considered materials were recorded. In overall the theoretical determination corroborates to the experimental findings. The phenomenon of the photon cascade emission is particularly stressed, being important for the design of modern phosphors with quantum efficiencies larger than 100%. (C) 2014 Elsevier B.V. All rights reserved.