Effect of laser parameters on ultrafast hydrogen migration in methanol studied by coincidence momentum imaging.
The effect of intensity, duration, and polarization of ultrashort laser pulses (795 nm, 40-100 fs, and 0.15-1.5 × 10(15) W/cm(2)) on the hydrogen migration in methanol is systematically investigated using Coulomb explosion coincidence momentum imaging. The ratio of the ion yield obtained for the migration pathway CH(3)OH(2+) → CH(2)(+) + OH(2)(+) with respect to the sum of the yields obtained for the migration pathway and for the nonmigration pathway CH(3)OH(2+) → CH(3)(+) + OH(+) exhibits a small (10-20%) but clear dependence on laser pulse properties, that is, the ratio decreases as the laser peak intensity increases but increases when the pulse duration increases as well as when the laser polarization is changed from linear to circular.
Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan.
Huailiang
H
Xu
Tomoya
T
Okino
Tatsuya
T
Kudou
Kaoru
K
Yamanouchi
Stefan
S
Roither
Markus
M
Kitzler
Andrius
A
Baltuska
See-Leang
SL
Chin