Volume 111, Issue 3, 15 July 1999
Index of content:
111(1999); http://dx.doi.org/10.1063/1.479365View Description Hide Description
The spectral line shapemodel recently proposed by the present authors [J. Chem. Phys. 109, 8283 (1998)] is extended in order to account for correlation between velocity- and phase-changing collisions. The possible additional source of asymmetry due to the finite duration of collision is also included. In this implemented form, the model is consistent with previous exhaustive experimental studies in the collision regime for –rare gases and –nitrogen mixtures and has been shown to also accurately describe the observed spectral features at lower pressure for It should be pertinent for various other molecular systems in a wide range of pressure and temperature, in particular for optical diagnostics.
Wavelength-resolved stimulated photon echoes: Direct observation of ultrafast intramolecular vibrational contributions to electronic dephasing111(1999); http://dx.doi.org/10.1063/1.479366View Description Hide Description
Novel wavelength-resolved stimulated photon echomeasurements on a dye molecule in solution are presented. Data are simulated within the multimode Brownian oscillator model using the spectral density of de Boeij et al. [J. Phys. Chem. 100, 11806 (1996)] for the same solute–solvent system. For photon echo population times fs there are considerable differences between the measured and calculated data. Aided by further simulations, we conclude that these discrepancies result from dephasing dynamics of high frequency intramolecular vibrational modes not included in the previously derived spectral density.