Vs. Pavlovich et Sv. Zablotsky, SOLVATION OF EXCITED MOLECULES OF POLAR C OMPOUNDS BY POLAR-SOLVENT AND KINETICS OF FLUORESCENCE-SPECTRA, Doklady Akademii nauk BSSR, 38(4), 1994, pp. 31-35
We have investigated kinetics of instantaneous fluorescence of phthali
mides and 2-acetilanthracene in isobutyl and propyl alcohols at delay
times from 2,5 to 70 ns that is 3-4 times the average lifetime in the
excited state. It has been found that side by side with usual long-wav
e shift of the fluorescence band at a later stage of relaxation a reve
rse shift of the band to the opposite region is observed. The shift of
the spectrum is accompanied by considerable broadening of the band (p
hthalimides) and disturbance of the McCoy and Ross relations for vibra
tional bands intensities active in the oscillation spectrum (2-acetyla
nthracene). The change of the direction of the band shift indicates th
at the Debye model cannot be used for describing the process of excite
d molecules solvation by solvent. The reverse shift is accounted for b
y different mobility of solvent molecules in coordination layers of th
e solvent shell.