We report the results of a theoretical study of low-energy electron-${\mathrm{NH}}_3$ scattering in which target polarization effects are included by using an ab initio optical potential. The calculations employ the complex Kohn variational technique and are undertaken at both the static-exchange and polarized-self-consistent-field levels. Particular attention is paid to the complications attending electron scattering from target molecules that possess a permanent dipole moment. We describe the steps necessary to extract meaningful differential cross sections from fixed-nuclei calculations that ignore the rotational motion of the target. Good agreement is found between our results and recent experimental measurements.

• Received 3 January 1992

DOI:https://doi.org/10.1103/PhysRevA.45.7800