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arXiv · 1904.01515

Diffractive imaging of dissociation and ground state dynamics in a complex molecule

Kyle Wilkin·Robert Parrish·Jie Yang·Thomas J. A. Wolf·Pedro Nunes·Markus Guehr·Renkai Li·Xiaozhe Shen·Qiang Zheng·Xijie Wang·Todd J. Martinez·Martin Centurion
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Abstract

We have investigated the structural dynamics in photoexcited 1,2-diiodotetrafluoroethane molecules (C2F4I2) in the gas phase experimentally using ultrafast electron diffraction and theoretically using FOMO-CASCI excited state dynamics simulations. The molecules are excited by an ultra-violet femtosecond laser pulse to a state characterized by a transition from the iodine 5p orbital to a mixed 5p|| hole and CF2 antibonding orbital, which results in the cleavage of one of the carbon-iodine bonds. We have observed, with sub-Angstrom resolution, the motion of the nuclear wavepacket of the dissociating iodine atom followed by coherent vibrations in the electronic ground state of the C2F4I radical. The radical reaches a stable classical (non-bridged) structure in less than 200 fs.

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Kyle Wilkin, Robert Parrish, Jie Yang, Thomas J. A. Wolf, Pedro Nunes, Markus Guehr, Renkai Li, Xiaozhe Shen, Qiang Zheng, Xijie Wang, Todd J. Martinez, Martin Centurion. 2019-04-02. Diffractive imaging of dissociation and ground state dynamics in a complex molecule. https://doi.org/10.1103/physreva.100.023402

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