C-Cl and C-H bond cleavage in 193 nm photodissociation of CH3CF2Cl and CH3CFCl2 Academic Article uri icon


  • The relative amounts of Cl (2 P 3/2)[Cl], Cl (2 P 1/2)[Cl*], H, and HCl produced by 193 nm photodissociation of CH 3 CF 2 Cl and CH 3 CFCl 2 were studied by a laser pump-and- probe technique. An excimer laser photodissociated the parent molecules and a frequency doubled tunable dye laser probed the photofragments via (2+ 1) resonantly enhanced multiphoton ionization coupled with a time-of-flight mass spectrometer. Only atomic products were observed; no HCl was found. The profiles were well fitted to Gaussians. The Cl*/Cl branching ratios were almost identical, 0.18±0.04 and 0.16±0.04, while the H/(Cl+ Cl*) ratios were 0.67±0.21 and 0.18±0.07, for CH 3 CF 2 Cl and CH 3 CFCl 2, respectively. The mechanism for the production of the atomic species is discussed.

publication date

  • January 1, 1997