Due to its ubiquitous nature, SO2 has been a chromophore of spectroscopic interest for some time. However, its potential energy surface is very complex and many details of SO2 photolysis remain unknown. A femtosecond pump-probe technique was used to elucidate the temporal evolution of photoinduced wavepacket motion of this chromophore. The monomer transient rapidly decayed, exhibiting an excited state lifetime of 230 fsec. The corresponding product, SO, displayed a growth of 225 fsec in accord with the proposed mechanism resulting in S-O cleavage. The addition of sequential SO2 molecules to the cluster significantly altered the lifetime associated with the E state, resulting in an increase from 230 to 435 fsec for one to four SO2 units, respectively. This trend was consistent with the proposed dissociation mechanism. Molecular SO2 clusters were formed through van der Waals forces and as additional units are accommodated a steric force was exerted on the bending SO2, thereby impeding its achievement of a linear geometry. Dissociation of the molecular clusters proceeded differently than the SO2 molecule itself. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA 8/22-26/2004).
|Original language||English (US)|
|Number of pages||3|
|Journal||ACS, Division of Environmental Chemistry - Preprints of Extended Abstracts|
|State||Published - Dec 1 2004|
|Event||228th ACS National Meeting - Philadelphia, PA, United States|
Duration: Aug 22 2004 → Aug 26 2004
All Science Journal Classification (ASJC) codes