The energy parameters of colloidal seed centers in crystals were calculated for a model which consisted of an F center with a Li atom in its anion vacancy site. It was found that the results of the calculations agreed with the corresponding spectral position which was observed in the absorption band at 270nm.

B.D.Lobanov, V.M.Kostyukov, N.T.Maksimova, V.N.Salomatov, L.I.Shchepina, T.G.Yureva: Fizika Tverdogo Tela, 1995, 37[9], 2545-9 (Physics of the Solid State, 1995, 37[9], 1397-9)