Electron-impact rotationally elastic total cross sections for H2CO and HCOOH over a wide range of incident energy (0.01–2000 eV)

Abstract

This paper reports computational results of the total cross sections for electron impact on H 2 CO and HCOOH over a wide range of electron impact energies from 0.01 eV to 2 keV. The total cross section is presented as sum of the elastic and electronic excitation cross sections for incident energies. The calculation uses two different methodologies, below the ionization threshold of the target the cross section is calculated using the UK molecular R-matrix code through the QUANTEMOL-N software package while cross sections at higher energies are evaluated using the spherical complex optical potential formalism. The two methods are found to be consistent at the transition energy (∼15 eV). The present results are, in general, found to be in good agreement with previous experimental and theoretical results (wherever available) and, thus, the present results can serve as a benchmark for the cross section over a wide range of energy.

Computation of electron-impact rotationally elastic total cross sections for methanol over an extensive range of impact energy (0.1 – 2000 eV)

“…The results obtained from the two different methods are consistent and there is a smooth transition at the overlap of the two formalisms. Thus, it is possible to provide the total cross section over a wide range of impact energies from meV to keV for a variety of targets [43][44][45][46][47]. We have presented our results in graphical form (Figs.…”

Electron-impact ionization cross section of formic acid

“…There the outer valence Green function (ROVGF) calculations of correlated electron affinities and ionization potentials were performed, providing different input parameters for the two BEB model calculations. For this reason, one can observe the difference between the BEB model calculations used by Możejko [35] and Vinodkumar et al [34].…”

“…Vinodkumar et al [33] presented theoretical calculations of the total ionization cross sections for electron impact on FA using a multicenter group additivity rule for impact energies of 15-2000 eV. The same group performed calculations employing an Improved Complex Scattering Potential-ionization contribution (ICSP-ic) to obtain ionization cross sections from total inelastic cross sections for energies ranging from 10 eV to 5000 eV incorporating the binary-encounter-Bethe model (BEB) in the same energy range [34]. Additionally, cross sections for single electronimpact ionization of FA were calculated using the BEB model in the energy range from the ionization threshold of 11.31 eV [19] up to 4000 eV [35].…”

Theoretical total cross sections fore-SO2scattering over a wide energy range (0.1−2000 eV) revealing a 3.4-eV shape resonance

“…We therefore employed the R-matrix code to carry out ab initio calculations to find total (elastic plus electronic excitation) cross sections up to the ionization threshold of the target and the spherical complex optical potential (SCOP) method for calculating total (elastic plus inelastic) cross sections beyond the ionization threshold up to 2 keV [26]. The composite results obtained by combining them has been shown to be promising [21,22,26] as there is consistency in the data particularly at the transition energy (∼15 eV) where the two formalisms overlap. Hence the main incentive for the present work is threefold: (i) to detect the resonance structures at low energies, (ii) to provide total cross sections over an extensive range of impact energies, and (iii) to benchmark our results against previous experimental and theoretical data.…”

“…At low impact energies (below the ionization threshold of the target) we have carried out ab initio calculations using the R-matrix formalism through the Quantemol-N package [21][22][23][24], and above the threshold of the target, the SCOP formalism [25] is employed. Both the formalisms are well established and consistent over their respective range of impact energies.…”