EXCITED SfNGLET STATE DECAY PATHWAYS IN THE FLUORESCENCE PROBE MOLECULE
نویسنده
چکیده
The dec.~y of tlw eveitcd \ratc of 1,8-~nilioon~phthdlcnC 5ulpl1011at~ (ANS) In :~queous alld tShnndk solution Itas been studied by n:mosecond hscr flash photolys~~ The rntc of photoionizatton is found to increase rapidly a\ solvent pohty is increased and t\ the major decdy route in aqueous solution, wf:ercas m wn polar solvents intcr\yy9tcm crossing becomes an itnp~rt~nt decay process. The very low ~uffrc~cence yreld of ANS in water is thus interpreted as tteinq caused by very rapid photoloni;r&Jon from the iflltlalty cxcitcd singlet state.
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