Calculation of electron-impact rotationally elastic total cross sections for NH₃, H₂S, and PH₃ over the energy range from 0.01 eV to 2 keV

This paper report results of calculation of the total cross section QT for electron impact on NH3, H2S,and PH3 over a wide range of incident energies from 0.01 eV to 2 keV. Total cross sections QT (elastic plus electronic excitation) for incident energies below the ionization threshold of the target were calculated using the UK molecular R-matrix code through the Quantemol-N software package and cross sections at higher energies were derived using the spherical complex optical potential formalism. The two methods are found to give self-consistent values where they overlap. The present results are, in general, found to be in good agreement with previous experimental and theoretical results

Theoretical total cross sections for <i>e</i>-SO₂ scattering over a wide energy range (0.1−2000 eV) revealing a 3.4-eV shape resonance

We have used the ab initio R-matrix formalism at low impact energies (below the ionization threshold of the target) and the spherical complex optical potential methodology above the ionization threshold to generate total cross sections for e-SO2 scattering over the energy range from 0.1 to 2000 eV. The eigenphase diagram and total cross section indicate a structure at 3.4 eV which is ascribed to a shape resonance, evidence for which appears in earlier experimental studie

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

Theoretical rotationally elastic total cross sections for electron scattering from methanol over the incident energy range 0.1–2000 eV are presented. The computation of such cross sections for methanol is reported over such an extended energy range. We have employed two distinct formalisms to compute the cross sections across this energy range; between 0.1 eV and the ionization threshold of the target we have used the ab initio R-matrix method, while at higher energies the spherical complex optical potential method is invoked. The results from both formalisms match quite well at energies where they overlap and hence imply that they are consistent with each other. These total cross-section results are also in very good agreement with available experimental data and earlier theoretical data. The composite methodology employed here is well established and can be used to predict cross sections for other targets where data is scarce or not available

Electron interactions with astro chemical compounds

In present work electron induced processes with important astro-compounds found in the tholins of Titan are investigated. We report calculated total elastic cross sections Qel, total inelastic cross sections Qinel, total ionization cross sections Qion, total excitation cross sections ∑Qexc and total cross sections QT for hydrogen cyanide (HCN), cyanoacetylene (HCCCN), vinyl cyanide (CH2CHCN), methanimine (CH2NH) and ethanimine (CH3CHNH) on electron impact for energies from ionization threshold to 5 keV. We have employed the Spherical Complex Optical Potential (SCOP) formalism to investigate elastic as well as inelastic processes and used Complex Scattering Potential – ionization contribution (CSP-ic) method to derive ionization cross sections. In absence of any theoretical or experimental data of ionization cross sections except for HCN and HCCCN, we have computed Qion using the Binary- Encounter- Bethe (BEB) method for all these molecules and have found reasonable agreement. This is the maiden attempt to report various total cross sections for all these astro-molecules except HCN and HCCCN

Low energy electron interactions with Iodine molecule (I2)

A theoretical analysis is performed for electron interactions with the Iodine molecule (I2) for incident energies ranging from 0.1 eV to 20 eV. The calculations were carried out using Quantemol-N package, which uses the UK Molecular R-matrix Codes. Electron interactions with the I2 molecule have been studied with several target models in its equilibrium geometry, and the results are reported for the optimized target model. Scattering calculations are performed to provide resonance parameters along with Dissociative Electron Attachment (DEA) Cross-Sections. In addition, the study also focussed on the estimation of various cross-sections such as elastic, electronic excitation, differential, momentum transfer, ionization and total cross-sections. Many of these cross-sections reported here are for the first time for electron interaction with the iodine molecule to the best of our knowledge

Probing total cross sections for electron impact studies from meV to keV for H2S and PH3

In this paper we have computed total cross sections for H2S and PH3 using two different molecular codes, Quantemol N for low energy calculations and Spherical Complex Optical Potential for intermediate and high energies. The results are found to be in overall good agreement with available theoretical and experimental results

Theoretical electron impact total cross sections for tetrahydrofuran (C

We report electron impact total cross sections for tetrahydrofuran (C4H8O) from ionization threshold to 5 keV. We have employed Spherical Complex Optical Potential (SCOP) to calculate total cross sections QT, total inelastic cross sections Qinel and total elastic cross sections Qel and have used Complex Scattering Potential – ionization contribution (CSP-ic) formalisms to compute total ionization cross sections Qion and summed total excitation cross sections ∑ Qexc. We have compared our cross sections with available experimental as well as theoretical results and have found good agreement wherever available. This is the maiden attempt to report the total excitation cross sections for this target

Computation of electron impact scattering studies on benzene

An elaborate theoretical study of electron scattering with benzene over a broad impact energy range is reported in this article. Integrated cross sections such as the electronic excitation cross section, momentum transfer cross section, ionization cross section and the total collision cross section along with the differential elastic cross section are computed at low energy (0.01–20 eV) using ab initio R-matrix employing Quantemol-N. Beyond ionization threshold, the calculations are also carried out using spherical complex optical potential (SCOP) formalism up to 5000 eV. A smooth crossover of the total cross section data is obtained through the two formalisms at the incident energy equal to 13 eV and hence we are able to study the cross sections over a wide energy range. The scattering rate coefficients using the computed elastic cross sections for this target are reported for the first time