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arXiv · 1710.02372

Coulomb explosion imaging of concurrent CH$_{2}$BrI photodissociation dynamics

Michael Burt·Rebecca Boll·Jason W. L. Lee·Kasra Amini·Hansjochen Köckert·Claire Vallance·Alexander S. Gentleman·Stuart R. Mackenzie·Sadia Bari·Cédric Bomme·Stefan Düsterer·Benjamin Erk·Bastian Manschwetus·Erland Müller·Dimitrios Rompotis·Evgeny Savelyev·Nora Schirmel·Simone Techert·Rolf Treusch·Jochen Küpper·Sebastian Trippel·Joss Wiese·Henrik Stapelfeldt·Barbara Cunha de Miranda·Renaud Guillemin·Iyas Ismail·Loïc Journel·Tatiana Marchenko·Jérôme Palaudoux·Francis Penent·Maria Novella Piancastelli·Marc Simon·Oksana Travnikova·Felix Brausse·Gildas Goldsztejn·Arnaud Rouzée·Marie Géléoc·Romain Geneaux·Thierry Ruchon·Jonathan Underwood·David M. P. Holland·Andrey S. Mereshchenko·Pavel K. Olshin·Per Johnsson·Sylvain Maclot·Jan Lahl·Artem Rudenko·Farzaneh Ziaee·Mark Brouard·Daniel Rolles
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Abstract

The dynamics following laser-induced molecular photodissociation of gas-phase CH$_{2}$BrI at 271.6 nm were investigated by time-resolved Coulomb explosion imaging using intense near-IR femtosecond laser pulses. The observed delay-dependent photofragment momenta reveal that CH$_{2}$BrI undergoes C-I cleavage, depositing 65.6% of the available energy into internal product states, and that absorption of a second UV photon breaks the C-Br bond of CH$_{2}$Br. Simulations confirm that this mechanism is consistent with previous data recorded at 248 nm, demonstrating the sensitivity of Coulomb explosion imaging as a real-time probe of chemical dynamics.

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Michael Burt, Rebecca Boll, Jason W. L. Lee, Kasra Amini, Hansjochen Köckert, Claire Vallance, Alexander S. Gentleman, Stuart R. Mackenzie, Sadia Bari, Cédric Bomme, Stefan Düsterer, Benjamin Erk, Bastian Manschwetus, Erland Müller, Dimitrios Rompotis, Evgeny Savelyev, Nora Schirmel, Simone Techert, Rolf Treusch, Jochen Küpper, Sebastian Trippel, Joss Wiese, Henrik Stapelfeldt, Barbara Cunha de Miranda, Renaud Guillemin, Iyas Ismail, Loïc Journel, Tatiana Marchenko, Jérôme Palaudoux, Francis Penent, Maria Novella Piancastelli, Marc Simon, Oksana Travnikova, Felix Brausse, Gildas Goldsztejn, Arnaud Rouzée, Marie Géléoc, Romain Geneaux, Thierry Ruchon, Jonathan Underwood, David M. P. Holland, Andrey S. Mereshchenko, Pavel K. Olshin, Per Johnsson, Sylvain Maclot, Jan Lahl, Artem Rudenko, Farzaneh Ziaee, Mark Brouard, Daniel Rolles. 2017-10-06. Coulomb explosion imaging of concurrent CH$_{2}$BrI photodissociation dynamics. https://doi.org/10.1103/physreva.96.043415

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