The photoionization and photofragmentation dynamics of I2 in intense femtosecond near-infrared laser fields were studied using velocity-map imaging of cations, electrons, and anions. A series of photofragmentation pathways originating from different cationic electronic states were observed following single ionization, leading to I+ fragments with distinct kinetic energies, which could not be resolved in previous studies. Photoelectron spectra indicate that these high-lying dissociative states are primarily produced through nonresonant ionization from several molecular orbitals (MO) of the neutral. The photoelectron spectra also show clear signatures of resonant ionization pathways (Freeman resonances) to low-lying bound ionic states via Rydberg states of the neutral moiety. To investigate the role of these Rydberg states further, we imaged anionic products (I–) formed through ion-pair dissociations of neutral molecules excited to these Rydberg states by the intense femtosecond laser pulse. Collectively, these results shed significant new light on the complex dynamics of I2 molecules in intense laser fields and on the important role of neutral Rydberg states in a full description of strong-field phenomena in molecules.
Allum, Felix, et al. "Photoionization and Photofragmentation Dynamics of I<sub>2</sub> in Intense Laser Fields: A Velocity-Map Imaging Study." Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory, vol. 126, no. 46, Nov. 2022. https://doi.org/10.1021/acs.jpca.2c04379
Allum, Felix, McManus, Joseph, Denby, Oskar, Burt, Michael, & Brouard, Mark (2022). Photoionization and Photofragmentation Dynamics of I<sub>2</sub> in Intense Laser Fields: A Velocity-Map Imaging Study. Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory, 126(46). https://doi.org/10.1021/acs.jpca.2c04379
Allum, Felix, McManus, Joseph, Denby, Oskar, et al., "Photoionization and Photofragmentation Dynamics of I<sub>2</sub> in Intense Laser Fields: A Velocity-Map Imaging Study," Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory 126, no. 46 (2022), https://doi.org/10.1021/acs.jpca.2c04379
@article{osti_2006612,
author = {Allum, Felix and McManus, Joseph and Denby, Oskar and Burt, Michael and Brouard, Mark},
title = {Photoionization and Photofragmentation Dynamics of I<sub>2</sub> in Intense Laser Fields: A Velocity-Map Imaging Study},
annote = {The photoionization and photofragmentation dynamics of I2 in intense femtosecond near-infrared laser fields were studied using velocity-map imaging of cations, electrons, and anions. A series of photofragmentation pathways originating from different cationic electronic states were observed following single ionization, leading to I+ fragments with distinct kinetic energies, which could not be resolved in previous studies. Photoelectron spectra indicate that these high-lying dissociative states are primarily produced through nonresonant ionization from several molecular orbitals (MO) of the neutral. The photoelectron spectra also show clear signatures of resonant ionization pathways (Freeman resonances) to low-lying bound ionic states via Rydberg states of the neutral moiety. To investigate the role of these Rydberg states further, we imaged anionic products (I–) formed through ion-pair dissociations of neutral molecules excited to these Rydberg states by the intense femtosecond laser pulse. Collectively, these results shed significant new light on the complex dynamics of I2 molecules in intense laser fields and on the important role of neutral Rydberg states in a full description of strong-field phenomena in molecules.},
doi = {10.1021/acs.jpca.2c04379},
url = {https://www.osti.gov/biblio/2006612},
journal = {Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory},
issn = {ISSN 1089-5639},
number = {46},
volume = {126},
place = {United States},
publisher = {American Chemical Society},
year = {2022},
month = {11}}
SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Organization:
Engineering and Physical Sciences Research Council (EPSRC); USDOE Office of Science (SC)
Grant/Contract Number:
AC02-76SF00515
OSTI ID:
2006612
Journal Information:
Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory, Journal Name: Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory Journal Issue: 46 Vol. 126; ISSN 1089-5639
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 633https://doi.org/10.1016/j.nima.2010.06.178