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Published on: September 16, 2014
Conformational memory in photodissociation of formic acid
Leonid Khriachtchev1, Ermelinda Macoas, Mika Pettersson
1Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland. Leonid.Khriachtchev@Helsinki.Fi
Abstract:
The trans and cis forms of formic acid (HCOOH) in solid argon favor essentially different photodissociation (193 nm) products, H2O + CO and H2 + CO2, respectively. The branching ratio of these channels differs between the two conformers by a factor of >10. The observed selective photodissociation features conformational memory when the transition state of a molecule is reached before torsional randomization. These data demonstrate that the photodissociation products can be efficiently steered with selective narrow-band infrared radiation promoting rotational isomerism, which makes a strong case of optically controlled chemical reactions
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