Electron stopping power in biological compounds for low and intermediate energies with the generalized oscillator strength (GOS) model

The stopping power formula, based on the generalized oscillator strength (GOS) model, exchange correction and the inelastic differential cross-section (IDCS) given by Inokuti (Rev. Mod. Phys. 43(3) (1971) 297) is presented. With the aim of checking optical oscillator strengths (OOS), we calculated the values of the Bethe sum rule, f - sum, and the mean ionisation energy (MIE), I. Calculation of the stopping powers (SPs) for biological compounds: C5H5N5 (adenine), C5H5N5O (guanine), C4H5N3O (cytosine), C5H6N2O2 (thymine), C20H27N7O13P2 (cytosine-guanine) and C19H26N8O13P2 (thymine adenine) have been introduced for incident electrons in the 20 eV to 1 MeV energy range. A detailed comparison of the calculated data with other theoretical and experimental results for these biological elements and compounds is presented. The calculated results of stopping power for electrons in energy range from a few tens of electron volts to 1 MeV are found to be in good agreement to within 10% with the experimental data and theoretical data. (c) 2004 Elsevier Ltd. All rights reserved.