Regular Article

Elastic electron scattering by halocarbon radicals in the independent atom model approach^★

¹ Institute for Nuclear Research (ATOMKI), Bem tér 18/c, 4026 Debrecen, Hungary
² Institute of Electron Physics, National Academy of Sciences of Ukraine, Universitetska str. 21, 88017 Uzhhorod, Ukraine

^a e-mail: demes.sandor@atomki.mta.hu

Received: 25 October 2019
Received in final form: 1 February 2020
Published online: 19 March 2020

Abstract

In order to study the elastic scattering of electrons by CF_n (n = 1 − 4) molecular targets the independent atom model (IAM) is used with the optical potential (OP) method. The scattering cross sections were calculated in two approximations of the model – the IAM approach is used for the differential, while the Additivity Rule (IAM-AR) is used for the integral cross sections. The amplitudes of electron scattering by the carbon and fluorine atoms of the target molecules are calculated from the corresponding phase shifts, using the real and complex optical potential method. The parameter-free real part of the OP is calculated from the corresponding atomic characteristics – nuclear charge, electron density and static dipole polarizability. The differential and integral cross sections are calculated at equilibrium internuclear distances of the CF_n molecules. They were compared with the available experimental data and with other theoretical results. A good overall agreement was observed while comparing our integral cross sections with the measured data. The level of the agreement however strongly depends on the target molecule, and a good consistency is observed typically above certain collision energies: from 10 eV in case of CF₂, above 15-20 eV for CF₃ and from 40 eV in case of CF₄. Similar tendencies were found in case of the differential cross sections for a wide range of scattering angles at collision energies above 10 eV in case of CF₂, above 15–20 eV for CF₃, while in case of CF₄ – above 20 eV.