Simple model for the calculation of total cross sections for electron scattering from polyatomic molecules

The previously used additivity rule has been modified by considering the geometric shielding effect of molecules. Total cross sections (TCSs) for electron scattering from hydrocarbon molecules (C2H2, C2H4, C2H6, C3H6, C3H8 and C4H10) are calculated in 10-1000 eV employing this semiempirical approach. The atoms are presented by spherical complex optical potential which is composed of static, exchange, polarization, and absorption terms. Compared with our earlier results, the modified additivity rule for the TCS on complex polyatomic molecules is simple but more effective and it yields better accord with experiments in the intermediate and high energy region. (author)