Journal article
Femtosecond study of self-trapped vibrational excitons in crystalline acetanilide
Femtosecond IR spectroscopy of delocalized NH excitations of crystalline acetanilide confirms that self-trapping in hydrogen-bonded peptide units exists and does stabilize the excitation. Two phonons with frequencies of 48 and 76 cm(-1) are identified as the major degrees of freedom that mediate self-trapping.
After selective excitation of the free exciton, self-trapping occurs within a few 100 fs. Excitation of the self-trapped states disappears from the spectral window of this investigation on a 1 ps time scale, followed by a slow ground state recovery of the hot ground state within 18 ps.
Language: | English |
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Year: | 2002 |
Pages: | 067403 |
ISSN: | 10797114 and 00319007 |
Types: | Journal article |
DOI: | 10.1103/PhysRevLett.88.067403 |