Ultrafast Intramolecular and Caging Dynamics of I2 in CCl4 from Resonance Raman Spectroscopy

✍ Scribed by J. Xu; N. Schwentner; S. Hennig; M. Chergui

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 532 KB
• Volume: 28
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/(sici)1097-4555(199706)28:6<433::aid-jrs125>3.0.co;2-e

✦ Synopsis

The resonance Raman overtone progressions of in following excitation in the bound and continuum parts of I 2 CCl 4 the B state are presented. It is shown that the Raman contribution from the bound part is damped by predissociation as that of an outgoing wavepacket crossing over to the purely repulsive and B/ 1P 1u , 3P 2g , a 3P 1g aº 3R g -( 0) states. The Raman data deliver information about location and time of curve crossing events which is consistent with the previous results in liquid Xe and the femtosecond pump-probe studies in liquids. For excitation in the continuum part, the Raman overtone intensities show structures which are assigned to a coherent recoil of fragments in the cage. In addition, a broad structureless emission background appears for all excitation wavelengths shorter than 570 nm, which is assigned to incoherent recoils caused by vibrational relaxation and return of the I atoms in the Franck-Condon window of the B state to the ground state.