Electron Scattering By Methanol And Ethanol: A Joint Theoretical- Experimental Investigation

We present a joint theoretical-experimental study on electron scattering by methanol (CH 3OH) and ethanol (C 2H 5OH) in a wide energy range. Experimental differential, integral and momentum-transfer cross sections for elastic electron scattering by ethanol are reported in the 100-1000 eV energy range. The experimental angular distributions of the energy-selected electrons are measured and converted to absolute cross sections using the relative flow technique. Moreover, elastic, total, and total absorption cross sections for both alcohols are calculated in the 1-500 eV energy range. A complex optical potential is used to represent the dynamics of the electron-alcohol interaction, whereas the scattering equations are solved iteratively using the Padé's approximant technique. Our calculated data agree well with those obtained using the Schwinger multichannel method at energies up to 20 eV. Discrepancies at high energies indicate the importance of absorption effects, included in our calculations. In general, the comparison between our theoretical and experimental results, as well as with other experimental data available in the literature, also show good agreement. 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Electron impact ionization and fragmentation of biofuels

We present in this article, a review of our recent experimental and theoretical studies published in the literature on electron impact ionization and fragmentation of the primary alcohols methanol, ethanol, 1-propanol and 1-butanol (C1–C4). We discuss the mass spectra (MS) of these alcohols, measured for the electron impact energy of 70 eV and also, total (TICS) and partial (PICS) ionization cross sections in the energy range from 10 to 100 eV, which revealed the probability of forming different cations, by either direct or dissociative ionization. These experimental TICS are summarized together with theoretical values, calculated using the Binary-encounter Bethe (BEB) and the independent atom model with the screening corrected additivity rule (IAM-SCAR) methods. Additionally, we compared data of appearance energies – AE and discussed the application of the extended Wannier theory to PICS in order to produce the ionization and ionic fragmentation thresholds for the electron impact of these alcohols