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Updated: Jun 26, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
UV photodissociation of methyl bromide and methyl bromide cation studied by velocity map imaging
Valérie Blanchet1, Peter C Samartzis, Alec M Wodtke
1Laboratoire Collisions Agregats Reactivite, IRSAMC, Universite de Toulouse, UPS, F-31062 Toulouse, France. val@irsamc.ups-tlse.fr
Abstract:
We employ the velocity map imaging technique to measure kinetic energy and angular distributions of state selected CH(3) (v(2)=0,1,2,3) and Br ((2)P(3/2), (2)P(1/2)) 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 CH(3)Br(+) photodissociation near 330 nm. The excess energy of the probe laser photon is channeled into CH(3) (+) vibrational excitation, most probably in the nu(4) degenerate bend.
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