Hyperfine parameters from nonresonant luminescence effects and spin memory of F center pairs in alkali halides

In a static (100) magnetic field, the luminescence of F centers in KCl shows peaks at 1134, 1516, (790) G, attributed to 4th (3rd) nearest neighbouring nuclei with equal Zeeman and hyperfine energies. The electronic spin memory losses for KCl, NaCl and KBr are in the ratio 1: (4.5 ± 1): (11 ± 3).