Exciton interactions in crystalline tetracene studied by single picosecond pulse excitation

• Published in: Chemical physics letters 1977-01, Vol.48 (3), p.495-500
• Main Authors: Campillo, A.J., Hyer, R.C., Shapiro, S.L., Swenberg, C.E.
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/0009-2614(77)85079-3

The efficiency of fluorescence in crystalline tetracene was studied as a function of excitation intensity with single picosecond laser pulses. Theoretical fits to the experimental fluorescence-quenching curves, at room temperature and at 170 K, for both a and b-incident polarizations, gave a singlet-singlet annihilation rate of γ ss = 10 −7 cm 3 s −1, to within a factor of two. This rate constant was confirmed by directly measuring the dependence of fast radiative lifetimes on excitation intensity. We also infer a value for the singlet diffusion rate, D s, or 4 × 10 −2 cm 2 s −1 to within a factor of two.