Ionisation simple de petites molécules par impact d’électrons : application a NH3

Abstract

In this work, we have studied the ionization of the ammonia molecule (NH3) consisting on a four scattering center by electron impact in the framework of the Born approximation. A single center basis has been used reducing the molecular problem to an atomic one. At high energies, a good agreement is observed between our results and the experimental data. But at low energies, a fairly good agreement is observed between the experimental and theoretical results except for small ejected angles where our results overestimate clearly the experiments. This is due to the limit of validity of the Born1 approach at low impact energy; the results could be improved by Born2 approximation . The method is to be applied for other small molecules.