J. Azuma et al., FEMTOSECOND DYNAMICS AND STIMULATED-EMISSION FROM THE S-2 STATE OF A LIQUID-CRYSTALLINE TRANS-AZOBENZENE, Chemical physics letters, 288(1), 1998, pp. 77-82
The excited-state S-2 dynamics of an azobenzene derivative, trans-BMAB
, was investigated in solution by femtosecond transient absorption and
picosecond single-photon timing fluorescence spectroscopies. The fluo
rescence was observed at 400 nm with a lifetime similar to 250 fs. The
S-1 state with an absorption maximum at 410-415 nm was formed with a
time constant of similar to 250 fs from the S-2 state followed by rela
xation with a lifetime of similar to 2.3 ps in n-hexane. The stimulate
d emission from the S-2 state overlapped with the femtosecond transien
t absorption spectra just after excitation, which was confirmed by pol
arization absorption spectroscopy. (C) 1998 Elsevier Science B.V. All
rights reserved.