“…One possible answer to modern requirements could be xanthene dyes and their derivatives [ 1 ]. They have found applications in bioimaging [ 2 , 3 , 4 , 5 , 6 , 7 ], photonic [ 8 , 9 , 10 , 11 ] as well as optic sensors [ 12 , 13 , 14 , 15 , 16 ]. Although they have excellent spectroscopic properties (e.g., high quantum yields ~95%), some problems are also noticeable.…”