A detailed comparison of calculated and measured electron-impact ionization cross sections of atoms using the Deutsch-Mark (DM) formalism

We present a comprehensive comparison between the results of the recently revised DM formula, which now exhibits the quantum mechanically correct high-energy behavior, and measured atomic ionization cross sections for selected atoms covering a wide range of targets of different electronic structure as well as elements along columns of the periodic table. Specifically, we selected the following elements (listed in order of increasing atomic number Z): Na, Si, S, Cl, K, Ca, Fe, Ga, Br, In, Cs, Hg, Bi, and U. The main objective of this study is to compare the results of the revised DM formula for these elements in both the low- and high-energy regime with available experimental data and to extend the formalism to targets with higher atomic number Z, where contributions to the ionization cross section from f-electrons have to be considered. In cases, where several, sometimes conflicting experimental data sets have been reported, an attempt is made to provide guidance as to the reliability of various measured cross sections. In addition, we also calculated ionization cross sections for the technically important species Cr, Mn, and W, for which no experimental data are available. (c) 2005 Elsevier B.V. All rights reserved.