DEFECT CENTRES IN KMGF3 PRODUCED BY X-IRRADIATION AT ROOM TEMPERATURE

Optical and ESR examination of KMgF3 following X-irradiation at room temperature shows that the irradiation produces F centres, analogous to those defined for the alkali halides, with peak optical absorption at 280 nm and with g value of 2.00 and an isotropic hyperfine structure due to interaction with eight equivalent I= 1 2 nuclei. Another absorption band, at 440 nm, is tentatively proposed as an M band due to F centres on adjacent sites. Polarisation of the emission from this band, which peaks at 566 nm, is consistent with this interpretation. © 1969.