Abstract
The excitation cross-sections for the rotational and the vibrational transitions are calculated on the basis of the Born approximation combined with the point-dipole interaction. This calculation is partly the reconfirmation and partly a slight extension of the previous treatments. The validity of this treatment is examined. It is concluded that the treatment is not applicable for the incident energies around and above 1 eV because of an effect of large distortion in the wave function of the scattered electron. Possibilities of improving the theory are briefly discussed.