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In this paper, we report total cross sections for electron-induced ionization and excitations from both the excited metastable state H*2(c3Пu) 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(c3Пu). This work has potential applications in the fields of plasma physics and planetary atmospheres.

In this paper we report our calculations on several important total cross-sections (TCSs) of positron impact on isoelectronic N 2 and CO molecules, treated in the complex spherical potential formalism. Basically the total (complete) cross-section Q T consists of elastic and inelastic contributions. Our total inelastic cross-section (Q inel ) contains ionization and electronic excitations together with positronium formation. Our goal here is to bifurcate Q inel further to deduce total ionization cross-section, using the 'complex scattering potential-ionization contribution' (CSP-ic) method of electron-atom/molecule scattering. The present range of positron energy is 15-2000 eV. All the resulting cross-sections are in a good general accord with the existing data. This work highlights the importance of various scattering channels in e + -N 2 and e + -CO interactions at intermediate and high energies.

Electron impact ionization of SiCl X (X = 1-4) molecules is less studied but an important process for understanding and modelling the interactions of silicon-chlorine plasmas with different materials. The SiCl 3 radical is a major chloro-silicon species involved in the CVD (chemical vapour deposition) of silicon films from SiCl 4 /Ar microwave plasmas. We report in this paper the total ionization cross sections for electron collisions on these silicon compounds at incident energies from the ionization threshold to 2000 eV. We employ the 'complex scattering potential-ionization contribution' method and identify the relative importance of various channels, with ionization included in the cumulative inelastic scattering. New results are also presented on these exotic molecular targets. This work is significant in view of the paucity of theoretical studies on the radicals SiCl X (X = 1-3) and on SiCl 4 .

In this paper, we report theoretical electron impact ionization cross sections from threshold to 2000 eV for isocarbonic open chain molecules C4H6, C4H8, C4F6 including their isomers, and closed chain molecules c-C4H8 and c-C4F8. Theoretical formalism employed presently, viz., Complex Scattering Potential-ionization contribution method has been used successfully for a variety of polyatomic molecules. The present ionization calculations are very important since results available for the studied targets are either scarce or none. Our work affords comparison of C4 containing hydrocarbon versus fluorocarbon molecules. Comparisons of the present ionization cross sections are made wherever possible, and new ionization data are also presented.