Electron induced ionisation of C₃ to C₆ ethanoates

Abstract

5The present article reports calculation of electron impact total ionisation cross sections for C 3 to C 6 ethanoates for the energy range from ionisation threshold of the target to 5000 eV. The spherical complex optical potential and complex scattering potential ionisation contribution methods are employed to calculate the cross sections. The results presented here show consistent variation with previous measurements and theoretical values, wherever available. The dependence of isomeric effect on the ionisation cross section is also studied. Plot for the peak of ionisation cross section against the square root of the ratio of polarisability to

Electron induced ionization cross sections for astrophysical modelling

“…The ratio of Q ion to Q inel (R p ) at the peak (Eq. (7)) is found to be between 70 and 80% as reported by Turner et al [27] and Karwasz et al [28] This was also confirmed by the authors [16][17][18][19]. This causes an uncertainty which can be determined by calculating the cross section at the peak using R p = 0.60, 0.65, 0.7, 0.75 and 0.8.…”

“…The correlation between the maximum of ionization cross section versus square root of the ratio of polarizability to ionization potential of methyl and ethyl formates is plotted in Fig. 7 along with aldehyde, ketone, cycloalkane, and methyl and ethyl acetate from previously reported work [18,19]. The same correlation plot is employed to compute the polarizabilities of C 4 to C 6 formates, since polarizability volumes for these molecules are not available in the literature.…”

“…A series of calculations are performed for electron impact scattering studies of C 2 to C 6 formates by combining MSCOP and CSP-ic method [16][17][18][19]. The present electron impact total ionization cross sections for the formates are compared in Figs.…”

“…The MSCOP method is a coherent blend of Group Additivity Rule (GAR) [19] and spherical complex optical potential (SCOP) method [15][16][17][18][19]. Firstly, multiple scattering centres in a molecule are identified depending on the extend of electron charge density of each independent centre and then the SCOP method is employed to find the respective group's cross section.…”

“…Using this method, the inelastic cross section is calculated for each molecule in its gaseous ground state. The ionization cross section is then derived from the inelastic part by a semi empirical method called the complex scattering potentialionization contribution (CSP-ic) method [16][17][18][19]. The data are presented here over an energy range from the ionization threshold to 5 keV.…”