Luminescence of LiBaF3 and KMgF3 doped with Eu2+

In this contribution the results of the high pressure spectroscopy of LiBaF3 and KMgF3 doped with Eu2+, where high pressure was applied in a diamond anvil cell are summarized. Photoluminescence, time resolved luminescence and luminescence kinetics, at a pressure from ambient to 300 kbar, at 77 K and ambient temperature are shown and discussed. The LiBaF3:Eu2+ luminescence spectra consisted of sharp lines peaked at 27,500-28,000 cm(-1) attributed to the P-6(7/2) -> S-8(7/2) transitions in the 4f(7) electronic configuration of Eu2+ and a broad band extended between and 21,000 and 26,600 cm(-1), attributed to Eu2+ trapped exciton recombination. When the pressure increased the Eu2+ trapped exciton emission disappeared and was replaced by a sharper band peaked at 28,200 cm(-1) attributed to 4f(6)5d(1) (e(g)) -> 4f(7)(S-8(7/2)) transition in Eu2+ The KMgF3:Eu2+ luminescence contained only the sharp lines related to the P-6(7/2) -> S-8(7/2) transition of Eu2+ and was found to be pressure independent, up to 300 kbar. The differences in the emission spectra between LiBaF3:Eu2+ and KMgF3:Eu2+ are discussed in the context of the structure of Eu2+ sites in perovskite and inversed perovskite lattices. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.