A Complete Cross Section Data Set for Electron Scattering by Pyridine: Modelling Electron Transport in the Energy Range 0–100 eV

Filipe Costa,Alessandra S Barbosa,Ronald D White,Paulo Limão-Vieira,Alexander Dorn,Adrián García-Abenza,Jimena D Gorfinkiel,Xueguang Ren,Ana I Lozano,Michael J Brunger,Juan C Oller,Darryl B Jones,Lidia Álvarez,Gustavo García,Antonio Muñoz,Peter Stokes,Ali Traoré-Dubuis,Marcio H F Bettega,Francisco Blanco

doi:10.3390/ijms21186947

Abstract

Electron scattering cross sections for pyridine in the energy range 0–100 eV, which we previously measured or calculated, have been critically compiled and complemented here with new measurements of electron energy loss spectra and double differential ionization cross sections. Experimental techniques employed in this study include a linear transmission apparatus and a reaction microscope system. To fulfill the transport model requirements, theoretical data have been recalculated within our independent atom model with screening corrected additivity rule and interference effects (IAM-SCAR) method for energies above 10 eV. In addition, results from the R-matrix and Schwinger multichannel with pseudopotential methods, for energies below 15 eV and 20 eV, respectively, are presented here. The reliability of this complete data set has been evaluated by comparing the simulated energy distribution of electrons transmitted through pyridine, with that observed in an electron-gas transmission experiment under magnetic confinement conditions. In addition, our representation of the angular distribution of the inelastically scattered electrons is discussed on the basis of the present double differential cross section experimental results.

Highlights

In the last few years, we have paid considerable attention, within international collaborations, to the study of electron interactions with pyridine molecules
The measured double differential cross sections (DDCS) will be used to check the reliability of our semi-empirical angular distribution function used for describing inelastic processes, both of these quantities are subsequently used as the input data for the electron transport simulations
From the differential elastic cross sections calculated within these methods, and complemented with our IAM-SCAR calculations for energies above 20 eV, angular distribution functions have been derived for our modelling purposes

Summary

Introduction

In the last few years, we have paid considerable attention, within international collaborations, to the study of electron interactions with pyridine molecules (see [1,2,3] and references therein). Here we incorporate new electron energy loss distribution functions for the main inelastic processes (vibrational, electronic excitation and ionization), as measured with a standard electron transmission apparatus [7], and double differential ionization cross sections derived from a reaction microscope coincidence analysis [8,9,10] The reliability of this cross section data set is evaluated by comparing the simulated electron intensity transmitted through a well-defined molecular density of gaseous pyridine, under strong magnetic field confinement conditions, with that directly measured with an alternative electron transmission apparatus [11]. Our semi-empirical formulae for the differential inelastic cross sections, derived from two different approaches, will be evaluated by comparison with those electron microscope experimental results

Methods

Results

Discussion

Conclusion