Molecular Modes of Attosecond Charge Migration

Aderonke S. Folorunso, Louisiana State University
Adam Bruner, Louisiana State University
François Mauger, Louisiana State University
Kyle A. Hamer, Louisiana State University
Samuel Hernandez, Louisiana State University
Robert R. Jones, University of Virginia
Louis F. Dimauro, The Ohio State University
Mette B. Gaarde, Louisiana State University
Kenneth J. Schafer, Louisiana State University
Kenneth Lopata, Louisiana State University

Abstract

First-principles calculations are employed to elucidate the modes of attosecond charge migration (CM) in halogenated hydrocarbon chains. We use constrained density functional theory (DFT) to emulate the creation of a localized hole on the halogen and follow the subsequent dynamics via time-dependent DFT. We find low-frequency CM modes (∼1 eV) that propagate across the molecule and study their dependence on length, bond order, and halogenation. We observe that the CM speed (∼4 Å/fs) is largely independent of molecule length, but is lower for triple-bonded versus double-bonded molecules. Additionally, as the halogen mass increases, the hole travels in a more particlelike manner as it moves across the molecule. These heuristics will be useful in identifying molecules and optimal CM detection methods for future experiments, especially for halogenated hydrocarbons which are promising targets for ionization-triggered CM.