We employ the velocity map imaging technique to measure kinetic energy and angular distributions of state selected CH3 (v2=0,1,2,3) and Br (2P3/2, 2P1/2) photofragments produced by methyl bromide photolysis at 215.9 nm. These results show unambiguously that the Br and Br* forming channels result in different vibrational excitations of the umbrella mode of the methyl fragment. Low energy structured features appear on the images, which arise from CH3Br+ photodissociation near 330 nm. The excess energy of the probe laser photon is channeled into CH3+ vibrational excitation, most probably in the 4 degenerate bend. ©2009 American Institute of Physics
Voir en ligne : J. Chem. Phys., 130, 034304-11p (2009)