Issue 21, 2021

Ultrafast geometrical reorganization of a methane cation upon sudden ionization: an isotope effect on electronic non-equilibrium quantum dynamics

Abstract

The ultrafast structural, Jahn–Teller (JT) driven, electronic coherence mediated quantum dynamics in the CH4+ and CD4+ cations that follows sudden ionization using an XUV attopulse exhibits a strong isotope effect. The JT effect makes the methane cation unstable in the Td geometry of the neutral molecule. Upon the sudden ionization the cation is produced in a coherent superposition of three electronic states that are strongly coupled and neither is in equilibrium with the nuclei. In the ground state of the cation the few femtosecond structural rearrangement leads first to a geometrically less distorted D2d minimum followed by a geometrical reorganization to a shallow C2v minimum. The dynamics is computed for an ensemble of 8000 ions randomly oriented with respect to the polarization of the XUV pulse. The ratio, about 3, of the CD4+ to CH4+ autocorrelation functions, is in agreement with experimental measurements of high harmonic spectra. The high value of the ratio is attributed to the faster electronic coherence dynamics in CH4+.

Graphical abstract: Ultrafast geometrical reorganization of a methane cation upon sudden ionization: an isotope effect on electronic non-equilibrium quantum dynamics

Supplementary files

Article information

Article type
Paper
Submitted
08 Mar 2021
Accepted
29 Apr 2021
First published
30 Apr 2021

Phys. Chem. Chem. Phys., 2021,23, 12051-12059

Ultrafast geometrical reorganization of a methane cation upon sudden ionization: an isotope effect on electronic non-equilibrium quantum dynamics

C. E. M. Gonçalves, R. D. Levine and F. Remacle, Phys. Chem. Chem. Phys., 2021, 23, 12051 DOI: 10.1039/D1CP01029H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements