A Theoretical Study of Scattering of Electrons and Positrons by CO2 Molecule

Abstract

This article presents a theoretical investigation of the differential, integrated, elastic, inelastic, total, momentum-transfer, and viscosity cross-sections, along with the total ionization cross-section, for elastically scattered electrons and positrons from a carbon dioxide (CO2) molecule in the incident energy range of 1 eV ≤Ei≤ 1 MeV. In addition, for the first time, we report the spin polarization of e±−CO2 scattering systems. The independent atom model (IAM) with screening correction (IAMS) using a complex optical potential was employed to solve the Dirac relativistic equation in partial-wave analysis. The comparison of our results with the available experimental data and other theoretical predictions shows a reasonable agreement in the intermediate- and high-energy regions.

Electron and Positron Scattering Cross Sections from CO2: A Comparative Study over a Broad Energy Range (0.1–5000 eV)

“…This is a very surprising result, in clear contradiction with the experimental data, that will deserve further investigation. In addition, the TCS results for electron scattering from CO 2 , calculated by Billah et al, 80 are lower in magnitude than the present experimental reference data by about 48% at 5000 eV. With respect to the TCS for positrons, results from ref ( 80 ) are in reasonable agreement (within 10%) with the present calculation for impact energies above 20 eV but tend to be much lower in value below this energy.…”

“…In addition, the TCS results for electron scattering from CO 2 , calculated by Billah et al, 80 are lower in magnitude than the present experimental reference data by about 48% at 5000 eV. With respect to the TCS for positrons, results from ref ( 80 ) are in reasonable agreement (within 10%) with the present calculation for impact energies above 20 eV but tend to be much lower in value below this energy. Among other previous calculations, cited in ref ( 25 ), relevant to this study include positron data from Singh et al, 81 which are calculated with a spherical complex optical potential method.…”

“… Integral elastic cross sections (IECS) for electron and positron scattering by CO 2 . red −, present e-IECS calculation, blue −, present p-IECS calculation; red ---, e-IECS calculated by Billah et al; 80 blue ---, p-IECS calculated by Billah et al; 80 -·-, p-IECS from Singh et al 81 calculation; pink ▲, e-IECS recommended by Itikawa. 30 …”

“…The present calculated total scattering cross sections for electrons (e-TCS) and positrons (p-TCS), from 0.1 to 5000 eV, together with our recommended data for electrons are plotted in Figure . Representative experimental and theoretical TCS values available in the literature − are also included in this figure for comparison.…”

Perspectives of Gas Phase Ion Chemistry: Spectroscopy and Modeling

“…For this reason, and because of its simplicity, we consider it the best option for our application. The IAM approach has also proven to be successful for other polyatomic molecules down to energies of tens of eV [141][142][143]. For energies below 50 eV, the theoretical model can be supplemented with the large amount of experimental data in the literature for these two molecules [144][145][146][147][148].…”