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

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

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

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Comprehensive study on electron impact for acetylene molecule is performed in terms of eigenphase diagram, electronic excitation cross sections as well as total cross section calculations from 1 eV to 5000 eV in this article. Computation of cross section over such a wide range of energy is reported for the first time. We have employed two distinct formalisms to derive cross sections in these impact energies. From 1 eV to ionization threshold of the target we have used the ab initio R-matrix method and then spherical complex optical potential method beyond that. At the crossing point of energy, both theories matched quite well and hence prove that they are consistent with each other. The results presented here expectedly give excellent agreement with other experimental values and theories available. The techniques employed here are well established and can be used to predict cross sections for other targets where data are scarce or not available. Also, this methodology may be integrated to online database such as Virtual Atomic and Molecular Data Centre to provide cross section data required by any user