Investigation of vibrational effect on the (e, 2e) triple differential cross sections of 1b _3g orbital of ethylene molecule by multi-center distorted wave method

The vibrational motions are usually neglected when calculating (e,2e) triple differential cross sections (TDCSs) of molecules. Here, multi-center distorted-wave method (MCDW) has been modified by including molecular vibrations. This vibrational MCDW method is employed to calculate the TDCSs of 1b 3g orbital of ethylene at low (100 eV) and medium (250 eV) incident electron energies in coplanar asymmetric kinematic condition. The results show that molecular vibrations significantly influence the angular distributions of the TDCSs, especially in the binary region along momentum transfer near the Bethe ridge.