Electron impact ionization cross sections for chloroethanes

The present work reports electron impact total ionization cross sections for chlorine substituted ethane molecules viz. C2H4Cl2, C2H3Cl3, C2H2Cl4, C2HCl3 and C2Cl6 in their gaseous ground state for the incident electron energies ranging from ionization threshold to 5 keV. We have employed the spherical complex optical potential formalism and group additivity rule for the determination of inelastic cross sections. The total ionization cross section is derived from the total inelastic cross section using a semi-empirical method called complex scattering potential ionization contribution method. The results are compared with prior experimental and theoretical values wherever available and an overall reasonable agreement is found. In addition, a correlation is obtained between the maximum of ionization cross section versus the square root of the ratio of the polarisability to ionization potential. (C) 2014 Elsevier B.V. All rights reserved.