EPR AND PHOTOLUMINESCENCE OF CR3+ IONS IN CSCDF3 AND CSCAF3

EPR and photoluminescence measurements of chromium doped CsCdF3 and Cs CaF3 crystals have been performed. The two main EPR signals are associ ated with cubic and trigonal Cr3+ centers. The g factor, the parameter s of the hyperfine (HF) interaction with the Cr-53 nuclei and the supe rhyperfine (SHF) interaction with the six nearest neighbour fluorine n uclei have been derived for the cubic centers. For the trigonal ones t he g factor and the zero field splitting parameter have been obtained. Photoluminescence and lifetimes have been measured at 10 K. The obser ved phonon structure is associated with zero phonon lines (ZPL) and vi brational replicas of both cubic and trigonal centers. The frequencies of the phonon modes of the [CrF6](3-) complex involved in the structu re have been derived.