Investigating the ultraviolet photodissociation of bromocyclopropane with ultrafast electron diffraction
Abstract
We have studied the photodissociation of gas-phase bromocyclopropane by 200 nm wavelength ultraviolet radiation using ultrafast electron diffraction. Bromocyclopropane is a prototypical molecule in the study of organobromides, a class of molecules that have a significant impact on atmospheric ozone depletion through their photochemistry. Previous studies have revealed two possible reaction pathways for the photodissociation of bromine from bromocyclopropane; either the C–Br bond dissociates, leaving behind a cyclopropyl ring, or there is a concerted opening of the cyclopropyl ring along with the C–Br bond dissociation. In this work, both our experimental and simulation results indicate that the majority of the UV-photoexcited BCP molecules (88% ± 11% in the experiment) follow the first reaction pathway, in which the cyclopropyl ring remains closed after homolytic C–Br bond cleavage. This direct bond dissociation occurs within the experimental time resolution of 270 fs. In order to differentiate between the possible reaction end-products, both of which have diffraction signals dominated by the bromine atom, a new analysis method has been employed, which is more sensitive to the structure of the end-products.
Article Details
Journal Info
The Journal of Chemical Physics
American Institute of Physics
Authors (21)
Jackson Lederer
Department of Physics and Astronomy, University of Nebraska-Lincoln 1 , Lincoln, Nebraska 68588,
J. Pedro F. Nunes
Diamond Light Source Ltd 2 , Diamond House, Harwell Campus, Didcot OX11 0D,
Conor D. Rankine
Department of Chemistry
Andrew R. Attar
SLAC National Accelerator Laboratory 4 , Menlo Park, California 94025,
Kareem Hegazy
SLAC National Accelerator Laboratory 4 , Menlo Park, California 94025,
Fuhao Ji
SLAC National Accelerator Laboratory 4 , Menlo Park, California 94025,
Cuong Le
Department of Physics and Astronomy, University of Nebraska-Lincoln 1 , Lincoln, Nebraska 68588,
Ming-Fu Lin
SLAC National Accelerator Laboratory 4 , Menlo Park, California 94025,
Yusong Liu
Duan Luo
Andrew J. Orr-Ewing
School of Chemistry
Sajib Kumar Saha
Department of Physics and Astronomy, University of Nebraska-Lincoln 1 , Lincoln, Nebraska 68588,
Xiaozhe Shen
SLAC National Accelerator Laboratory 4 , Menlo Park, California 94025,
Xijie Wang
Faculty of Physics, University of Duisburg-Essen 6 , 47048 Duisburg,
Matthew Ware
Stanford PULSE Institute, SLAC National Accelerator Laboratory 8 , Menlo Park, California 94025,
Stephen P. Weathersby
SLAC National Accelerator Laboratory 4 , Menlo Park, California 94025,
Kyle J. Wilkin
Department of Physics and Astronomy, University of Nebraska-Lincoln 1 , Lincoln, Nebraska 68588,
Thomas J. A. Wolf
Stanford PULSE Institute
Yanwei Xiong
Department of Physics and Astronomy, University of Nebraska-Lincoln 1 , Lincoln, Nebraska 68588,
Jie Yang
Martin Centurion
Department of Physics and Astronomy, University of Nebraska-Lincoln 1 , Lincoln, Nebraska 68588,