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

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.

arXiv comment13 pages, 11 figures

References in corpus (4)

• Imaging the Photochemical Ring-Opening of 1,3-Cyclohexadiene by Ultrafast Electron Diffraction
• Diffractive Imaging of Coherent Nuclear Motion in Isolated Molecules
• Diffractive imaging of a molecular rotational wavepacket with femtosecond Megaelectronvolt electron pulses
• Imaging of Alignment, Deformation and Dissociation of CS2 Molecules using Ultrafast Electron Diffraction

Cited by in corpus (2)

• Ultrafast Electron Diffraction: Visualizing Dynamic States of Matter
• Retrieval of missing small-angle scattering data in gas-phase diffraction experiments