Low-energy electron-impact excitation of the ã^3 B_(1u) (π→π∗) state of ethylene

A two‐state close‐coupling calculation of electron‐impact excitation of ethylene to the ã ^3B_(1u) state (π→π*) is carried out using a version of the Schwinger multichannel method developed for distributed‐memory parallel computers. The calculated integral cross section shows a sharp rise at threshold, in agreement with available experimental data. The integral and differential cross sections are useful in understanding the mechanism of this excitation process and indicate the possible presence of a core‐excited shape resonance near threshold