Vibrational excitation in the e+CO2 system: Nonlocal model of ΣΠ vibronic coupling through the continuum

Article

Vibrational excitation in the e+CO2 system: Nonlocal model of ΣΠ vibronic coupling through the continuum

Jan Dvořák; Karel Houfek; Martin Čížek

Phys. Rev. A 105(6), 062821 (2022)

Abstract

We present our model of the e+CO2 system that has been used to calculate the two-dimensional electron energy-loss spectrum of CO2 for incoming electron energies up to 5 eV reported in our Letter [Phys. Rev. Lett. 129, 013401 (2022)]. We derive the effective Hamiltonian that describes the nonlocal dynamics of CO2− within the full vibrational space and in the presence of the 2Σg+ virtual state and the Renner-Teller coupled 2Πu shape resonance. The electronic states are represented by three discrete states that interact directly with each other and also indirectly through the electronic continuum that consists of s and p partial waves. Based on our ab initio fixed-nuclei R-matrix calculations, parameters of the model are determined using a fitting procedure that utilizes the high symmetry of the system. The topology of the resulting complex potential energy surfaces is discussed. The model is constructed in such a way that the Hamiltonian expressed in a harmonic vibrational basis of the neutral molecule is a sparse matrix which enabled us to solve the multidimensional dynamics of vibrational excitation using iterative methods based on Krylov subspaces.

Institute authors

Supported by

GACR 19-20524S — Electron-driven atomic and molecular processes - development of ab initio methods

BibTeX

@article{UTF869,
  author        = {Jan Dvořák and Karel Houfek and Martin Čížek},
  title         = {{Vibrational excitation in the e+CO2 system: Nonlocal model of ΣΠ vibronic coupling through the continuum}},
  journal       = {Phys. Rev. A},
  volume        = {105},
  number        = {6},
  pages         = {062821},
  year          = {2022},
  doi           = {10.1103/PhysRevA.105.062821},
}