Excitation energy transfer between two 2i sites in triclinic L-EuBO3 and L-GdBO3 : EU3+

Analysis of the excitation of Eu3+ ions in site A and site B in L-EuBO3 and L-GdBO3:Eu3+ at several temperatures have shown very efficient energy tran sfer and reciprocal processes between both sites. At 12 K, the transfer fro m site A to site B dominates the process and results in the fluorescence qu enching of site A in L-EuBO3. At higher temperature, 77 and 300 K, the tran sfer and back transfer have nearly an equal rate and accordingly the same s pectra from both sites are obtained despite of exciting site A or site B. ( C) 2000 Elsevier Science S.A. All rights reserved.