Observing the Structural Evolution in the Photodissociation of Diiodomethane with Femtosecond Solution X-Ray Scattering
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Updated: Nov 26, 2025

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Matthijs R Panman1, Elisa Biasin2, Oskar Berntsson1
1Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 40530 Gothenburg, Sweden.
Abstract:
Resolving the structural dynamics of the initial steps of chemical reactions is challenging. We report the femtosecond time-resolved wide-angle x-ray scattering of the photodissociation of diiodomethane in cyclohexane. The data reveal with structural detail how the molecule dissociates into radicals, how the radicals collide with the solvent, and how they form the photoisomer. We extract how translational and rotational kinetic energy is dispersed into the solvent. We also find that 85% of the primary radical pairs are confined to their original solvent cage and discuss how this influences the downstream recombination reactions.
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