PHONON STRUCTURE OF CR3-DOPED MAF(3) (M=CD, CA A=RB, CS) CRYSTALS( PHOTOLUMINESCENCE IN CHROMIUM)

Citation
B. Villacampa et al., PHONON STRUCTURE OF CR3-DOPED MAF(3) (M=CD, CA A=RB, CS) CRYSTALS( PHOTOLUMINESCENCE IN CHROMIUM), Journal of luminescence, 63(5-6), 1995, pp. 289-296
Citations number
17
Categorie Soggetti
Optics
Journal title
ISSN journal
00222313
Volume
63
Issue
5-6
Year of publication
1995
Pages
289 - 296
Database
ISI
SICI code
0022-2313(1995)63:5-6<289:PSOCM(>2.0.ZU;2-Y
Abstract
The structure of the luminescence band of Cr3+ ions in CsCaF3, CsCdF3, RbCaF3 and RbCdF3 has been measured and analyzed using decay time mea surements and time-resolved spectroscopy. The observed emission corres ponds, in cubic Cr3+ centers, to the transition from the lowest spin-o rbit (SO) component of the T-4(2g)(F-4) level to the (4)A(2g)(F-4) gro und state. The structure has been associated with the zero phonon line s (ZPL) and vibrational replicas of several types of Cr3+ centers, mai nly cubic and trigonal ones. Four different phonon modes have been fou nd in each of the crystals. Their frequencies change with the host cry stal but not with Cr3+ symmetry. A tentative assignment of these phono n frequencies to normal modes of the [CrF6](3-) complex has been propo sed and discussed. The Cs compounds show a satellite at 14 cm(-1) in t he high energy side of each of the lines. It has been associated with the emission from the next SO component of the T-4(2g) level. The stro ng reduction of the SO coupling constant with respect to the free ion value is likely due to a dynamic Jahn-Teller effect.