Differential cross sections for elastic electron scattering. Charge-cloud polarization inH2

Relative elastic differential cross sections for electrons scattered from ${\mathrm{H}}_2$ have been measured for angles between 3 and 130 deg and electron energies between 100 and 1000 eV. The data agree very well with the first Born theory by Ford and Browne, and Liu and Smith for angles larger than 30 deg; however, strong deviations are found in the small-angle range. This discrepancy is discussed from the point of view of charge-cloud polarization and its adiabatic limit. It was found that the cross sections have not yet reached the adiabatic limit at 100 eV. The differential cross sections are integrated, and the total elastic cross sections are determined. The present values continue smoothly to the results of Truhlar et al. and are compatible with those of Ulsh, Wellenstein, and Bonham.