Energieübertragung zwischen gleich-und ungleichartigen Molekülen in Lösung III. Experimente über Fluoreszenzlöschung durch absorbierende Fremdstoffe/ Energy Transfer Among Like and Unlike Molecules in Solution III. Study of Fluorescence Quenching by Foreign Absorbing Substances

Abstract

Abstract Energy Transfer Among Like and Unlike Molecules in Solution 111. Study of Fluorescence Quenching by Foreign Absorbing Substances Radiationless energy transfer between unlike molecules (heterotransfer) in fluid solutions was studied by the quenching of fluorescence by foreign absorbing substances. The quenching of electronic excitation energy of 2-aminopurine and 2-aminopyrimidine, acting as sensitizers, and by acridine or 9-methylanthracene, acting as acceptors, was investigated in ethanol and compared with the theory of "multi-shell model" of a luminescent centre. In fluid solutions the critical distance for energy transfer is little depended on the diffusion. Good agreement was found with the equation taking into account only the excitation energy migration.