화학공학소재연구정보센터
Journal of Physical Chemistry, Vol.100, No.19, 7956-7961, 1996
Probing Curve Crossing by Wavelength-Dependent Recoil Anisotropy - The Photodissociation of CF3I at 275-303 nm Studied by Photofragment Translational Spectroscopy
Polarized photofragment translational spectroscopy was used to investigate the photodissociation process CF3I --> CF3 + I(P-2(3/2)) and CF3I --> CF3 + I*(P-2(1/2)) in the A absorption band between 275 and 303 nm. We determined the fragment recoil anisotropies beta(I) and beta(I*) and the branching ratio of the products I and I* as a function of the excitation wavelength lambda(exc) which covers most of the overlapping transitions (3)Q(1) <-- X and (3)Q(0) <-- X. The results are interpreted within the mechanistic scheme that involves three potential energy surfaces (3)Q(1), (3)Q(0), and (1)Q(1). The variation in the anisotropy beta(I*) and the product-yield ratio I/I* with lambda(exc) is shown to reflect the variation of mixed (3)Q(0) and (1)Q(1) character of the adiabatic states when excited near the avoided curve crossing.