O. Przhonska et al., EXCITED-STATE RELAXATION PROCESSES IN POLYMETHINE DYE MOLECULES IN POLYMERIC MEDIA, Journal of luminescence, 69(2), 1996, pp. 105-113
The fluorescence decay kinetics of polymethine dye molecules in liquid
(ethanol) and solid (polyurethane acrylate) media has been measured.
Absorption-relaxation-emission processes are studied at wide range of
excitation wavelengths (from blue to red edge of absorption band), emi
ssion wavelengths (including anti-Stokes fluorescence) and of temperat
ure (both in elastic and glassy states of polymeric medium). Time-reso
lved fluorescence spectra of dye molecules in polymer confirm that, in
spite of macrorigidity of polymeric medium, the characteristic time o
f relaxation processes within the excited state is comparable to the f
luorescence lifetime.