{'fraction_non_alphanumeric': 0.01456953642384106, 'fraction_numerical': 0.006622516556291391, 'mean_word_length': 4.90625, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Cerium-doped fluorescent and scintillating ionic crystals

Abstract Relaxation of electronic excitations created by the absorption of a high energy photon is analyzed in the case of rare earth crystals. it is shown that the energy transfer to cerium ions strongly depends on the band structure of the system, in particular on the position of the Ce 4f level in the bandgap. The probability of the hole capture by Ce3+ is related to the scintillation efficiency; it is in general weak in fluorides and stronger in oxides. The fact that cerium has two stable valence states Ce3+ and Ce4+ can lead to Ce bound exciton formation and Ce3+ low energy photoionization processes which can influence the fluorescence and scintillation efficiencies of the crystals.