Differential cross sections for the electron impact excitation of pyrimidine.

We report on differential cross section (DCS) measurements for the electron-impact excitation of the electronic states of pyrimidine. The energy range of the present measurements was 15-50 eV with the angular range of the measurements being 10°-90°. All measured DCSs displayed forward-peaked angular distributions, consistent with the relatively large magnitudes for the dipole moment and dipole polarizability of pyrimidine. Excitations to triplet states were found to be particularly important in some energy loss features at the lower incident electron energies. To the best of our knowledge there are no other experimental data or theoretical computations against which we can compare the present results.