Solution dynamics by line shape analysis, resonance light scattering and femtosecond four-wave mixing

Erik T.J. Nibbering, Koos Duppen, Douwe A. Wiersma

OnderzoeksoutputAcademicpeer review

33 Citaten (Scopus)
230 Downloads (Pure)

Samenvatting

The results of line shape analysis, resonance light scattering and femtosecond four-wave mixing measurements are reported on several organic molecules in solution. It is shown that a Brownian oscillator model for line broadening provides a full description for the optical dynamics in aprotic solutions. The dynamics of all systems studied is found to occur in the intermediate modulation regime, where the amplitude Δ and inverse correlation time Λ of the Brownian oscillator are about equal: Δ/Λ ≈ 1. Isotopic substitution of either probe or solvent is shown to have no effect on the dynamics, from which it is concluded that the vibrational force field plays a minor role in determining the line shape. Four-wave mixing experiments with chirped femtosecond pulses yield intense coherent Raman scattering signals due to ground and excited-state vibrational coherences which are very effectively driven by the two instantaneous light fields whose frequency difference matches exactly a vibrational mode. It is shown that the “chirped” four-wave mixing signal near zero delay time only mimics the two-pulse photon echo if the system dynamics fall in the fast modulation limit: Δ/Λ « 1. Otherwise this signal is damped not only by dephasing but also by solvation dynamics.
Originele taal-2English
Pagina's (van-tot)347-370
Aantal pagina's24
TijdschriftJournal of photochemistry and photobiology a-Chemistry
Volume62
Nummer van het tijdschrift3
DOI's
StatusPublished - 15-jan.-1992
Evenement15TH INTERNATIONAL CONF ON PHOTOCHEMISTRY - , France
Duur: 28-jul.-19912-aug.-1991

Citeer dit