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UV photodissociation of methyl bromide and methyl bromide cation studied by velocity map imaging

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 Added by Valerie Blanchet
 Publication date 2009
  fields Physics
and research's language is English




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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 excitation 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 nu_4 degenerate bend



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