Picosecond time-resolved resonance Raman observation of the iso-CH2Cl-I and iso-CH2I-Cl photoproducts from the photoisomerization reactions of CH2ICl in the solution phase

We report a preliminary picosecond Stokes time-resolved resonance Raman investigation of the initial formation and subsequent decay of the photoproduct produced following 267 nm excitation of CH2ClI in acetonitrile solution. Density-functional theory computations were done for several probable photoproduct species. Comparison of these computational results and results from a recent femtosecond transient absorption study to our present picosecond resonance Raman spectra indicate that the iso-CH2Cl-I species is mainly produced and associated with the similar to 460 nm transient absorption band. The iso-CH2Cl-I species appears to decay and form appreciable amounts of the more stable iso-CH2I-Cl species that is associated with a similar to 370 nm transient absorption band after a few hundred ps. (C) 2001 American Institute of Physics.