Energy transfer between Eu2+ ions in RbMgF3 crystals

Time-resolved spectroscopy after pulsed nitrogen laser excitation was used to characterize the energy transfer between Eu²⁺ ions in different crystal field sites in RbMgF₃ crystals. The results are consistent with electric dipole—dipole interaction and indicate that the Eu²⁺ ions are forming clusters in this host. As temperature is raised, the upper crystal field components of the metastable states of the ions become thermally populated and this changes the characteristics of the transfer process.