Theoretical calculations of the total and ionization cross sections for electron impacton some simple biomolecules

In this paper we report total cross sections TCS, QT, total elastic cross sections, Qel, and total ionization cross section, Qion for electron impact on water, formaldehyde, formic acid, and the formyl radical from circa 15 eV to 2 KeV. The results are compared where possible, with previous theoretical and experimental results and, in general, are found to be in good agreement. The total and elastic cross sections for HCHO, HCOOH, and CHO radical are reported

Total and ionization cross sections of electron scattering by fluorocarbons

Electron impact total cross sections (50-2000 eV) and total ionization cross sections (threshold to 2000 eV) are calculated for typical plasma etching molecules CF4, C2F4, C2F6, C3F8 and CF3I and the CFx (x = 1-3) radicals. The total elastic and inelastic cross sections are determined in the spherical complex potential formalism. The sum of the two gives the total cross section and the total inelastic cross section is used to calculate the total ionization cross sections. The present total and ionization cross sections are found to be consistent with other theories and experimental measurements, where they exist. Our total cross section results for CFx (x = 1-3) radicals presented here are first estimates on these species

Theoretical total ionization cross sections of CHx, CFx SiHx SiFx (x =1 – 4) and CCl4 targets by electron impact

Total ionization cross-sections of electron impact are calculated for the molecular targets CHx, CFx, SiHx, SiFx (x = 1-4) and CCl4 at incident energies 20-3 000 eV. The calculation is based on Complex Scattering Potential approach, as developed by us recently. This leads to total inelastic cross-sections, from which the total ionization cross-sections are extracted by reasonable physical arguments. Extensive comparisons are made here with the previous theoretical and experimental data. The present results are satisfactory except for the CFx and SiFx (x = 1-3) radicals, for which the experimental data are lower than most of the theories by more than 50%

Electron-impact total cross sections for inelastic processes for furan, tetrahydrofuran and 2,5-dimethylfuran

We report total inelastic, total ionisation and summed total excitation cross sections for electron scattering on furan, tetrahydrofuran (THF) and 2,5-dimethylfuran at energies between the ionisation threshold and 5 keV. We have employed the spherical complex optical potential formalism (SCOP) to calculate the total inelastic cross sections (Qinel) and have used complex scattering potential-ionisation contribution (CSP-ic) method to derive total ionisation cross sections (Qion) and summed total excitation cross sections (Qexc) from the calculated Qinel. We have also computed Qion for these molecules using binary-encounter-Bethe (BEB) approach. We have compared our total cross sections (TCS) with available experimental as well as previous theoretical results and have found good agreement. The results are presented graphically as well as numerically

Electron scattering with metastable H*2(c 3Πu) molecules: Ionization and other total cross sections

In this paper, we report total cross sections for electron-induced ionization and excitations from both the excited metastable state H*2(c3u) and the electronic ground state of H2. Total cross sections are reported for incident energies from the ionization threshold to 2000 eV using the 'complex scattering potential - ionization contribution' method and the relative importance of various scattering channels, including super-elastic scattering and ionization, are identified. There appear to be no previous data on the ionization cross sections for the metastable target H*2(c3u). This work has potential applications in the fields of plasma physics and planetary atmospheres

Electron impact calculations of total elastic cross sections over a wide energy range – 0.01 eV to 2 keV for CH₄, SiH₄ and H₂O

In this paper we report the results of a new theoretical methodology for determining the total elastic electron scattering cross section, Qel, over a wide range of incident energies between 0.01 eV and 2 keV. We have combined results from the UK molecular R-matrix code using Quantemol-N software to determine Qel for incident energies between 0.01 eV and the ionization threshold of the target with calculations based on the spherical complex optical potential formalism for higher energies up to 2 keV. We present results for three selected molecular targets; CH4, SiH4 and H2O as exemplars of the methodology. The present results were found to be in good agreement with previous experimental and theoretical results. The total elastic cross sections for such a wide energy range are reported perhaps for the first time