The spectrum of F-center creation was measured in Tl-doped material under 12 to 32eV synchrotron irradiation. It was found that the creation efficiency of a stable F center was especially high at 15 to 17eV, and at 28 to 30eV, where the absorption of one photon led to the formation of an electron-hole pair or of 2 electron-hole pairs plus an exciton. It was suggested that these cases provided favorable conditions for the stabilization of mobile radiation defects. This was attributed to the association of interstitial halogen atoms, holes and cation vacancies.

A.Lushchik, M.Kirm, I.Kudryavtseva, C.Lushchik, I.Martinson, E.Vasilchenko: Journal of Electron Spectroscopy and Related Phenomena, 1996, 79, 39-42