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Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Photodissociation dynamics of propargylene, HCCCH
Jens Giegerich1, Jens Petersen, Roland Mitrić
1Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany. roland.mitric@uni-wuerzburg.de ingo.fischer@uni-wuerzburg.de.
Abstract:
We report a joint theoretical and experimental study on the photodissociation of the C3H2 isomer propargylene, HCCCH, combining velocity map imaging with nonadiabatic trajectory surface hopping calculations. Propargylene loses an H-atom, after laser excitation at around 250 nm, presumably to the T6 state. The photofragment angular distribution exhibits only a very small anisotropy, but the H-atom translational energy distribution extends to high energies and shows an expectation value of 〈fT〉, the fraction of excess energy released as translation, of 48%, outside the range expected for a statistical reaction mechanism. The computations suggest a predissociation in the T4-T6 state and lead to a translational energy distribution and photofragment angular distribution that match the experimentally observed ones very well.
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