Ultrafast excited state relaxation in long-chain polyenes

作者:Antognazza Maria Rosa*; Lueer Larry; Polli Dario; Christensen Ronald L; Schrock Richard R; Lanzani Guglielmo; Cerullo Giulio
来源:Chemical Physics, 2010, 373(1-2): 115-121.
DOI:10.1016/j.chemphys.2010.03.002

摘要

We present a comprehensive study, by femtosecond pump-probe spectroscopy, of excited state dynamics in a polyene that approaches the infinite chain limit. By excitation with sub-10-fs pulses resonant with the 0-0 S-0 -> S-2 transition, we observe rapid loss of stimulated emission from the bright excited state S-2, followed by population of the hot S-1 state within 150 fs. Vibrational cooling of S-1 takes place within 500 fs and is followed by decay back to S-0 with 1 ps time constant. By excitation with excess vibrational energy we also observe the ultrafast formation of a long-living absorption, that is assigned to the triplet state generated by singlet fission.

  • 出版日期2010-7-19