Vibrational analysis of the elpasolites Cs2NaAlF6 and Cs2NaGaF6 doped with Cr3+ ions by fluorescence spectroscopy
Research output: Contribution to journal › Journal article › Research › peer-review
Interest in 3d transition metal impurities in ionic crystals has increased due to their important role in the laser activity of these materials. Moreover, recent advances in tunable solid-state lasers and high-power semiconductor laser diode arrays have generated a strong interest in investigating new compounds that emit in the visible and near-infrared spectral regions. In particular, many optical studies have been devoted to Cr3+-doped fluoride crystals as a consequence of the high quality of some Cr3+-based laser materials. In the present investigation, the low-temperature emission spectra of Cr3+ ions in the hexagonal elpasolites Cs2NaAlF6 and Cs2NaGaF6 have been measured. Each compound has two crystallographically inequivalent octahedral sites for the Al3+ and Ga3+ ions that can be occupied by Cr3+ ions. For both materials, the luminescence spectrum presents two zero-phonon lines accompanied by a well-defined vibrational structure. The different peaks of the emission broad band are described in terms of phonons of the lattice and normal modes of the octahedral complex [CrF6]3-. A detailed analysis of the vibrational structure observed leads to the conclusion that the 2E and 4T2 excited states of the [CrF6]3- ion are displaced along the eg and a1g and probably the t2g coordinates.
Original language | English |
---|---|
Journal | Journal of Fluorescence |
Volume | 10 |
Issue number | 4 |
Pages (from-to) | 375-381 |
Number of pages | 7 |
ISSN | 1053-0509 |
DOIs | |
Publication status | Published - 1 Dec 2000 |
Externally published | Yes |
ID: 218267552