Abstract
Uniaxial stress applied to KMgF3:Fe samples reveals that the ground state of the ion, which emits photoluminescence peaks in the 14000 cm-1 region at low temperature (2K), is a singlet orbital state. X-ray irradiation and heat treatment in O2 and H2 atmospheres together with high-temperature spectra (30K) of the KMgF3:Fe samples show that the most probable ion is Fe3+, the observed transitions being 4T1 to 6A1.