Ultrafast excited state relaxation in long-chain polyenes

Autor: Ronald L. Christensen, Dario Polli, Larry Lüer, Maria Rosa Antognazza, Richard R. Schrock, Giulio Cerullo, Guglielmo Lanzani
Rok vydání: 2010
Předmět:
Zdroj: Repositorio Institucional del Instituto Madrileño de Estudios Avanzados en Nanociencia
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ISSN: 0301-0104
DOI: 10.1016/j.chemphys.2010.03.002
Popis: 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.
Databáze: OpenAIRE