The ability of a mesogenic europium(III) beta-diketonate complex fixed on a quartz substrate by drying a highly concentrated solution of the complex in carbon tetrachloride to reduce the luminescence brightness of Eu3+ ions during prolonged UV laser irradiation and to spontaneously restore the initial luminescence parameters when kept in the dark for at least 22 hours at room temperature has been experimentally established.
Lapaev et al. (Wed,) studied this question.