Elastic and Electronically Inelastic Cross Sections for the Scattering of Electrons by Pyrrole.

Integral and differential cross sections for elastic and electronically inelastic electron scattering from the pyrrole molecule are reported. The cross section calculations employed the Schwinger multichannel method with norm-conserving pseudopotentials. The collision dynamics was described according to a model in which up to 209 energetically accessible channels were treated as open. In the elastic channel, calculations carried out in the interval of energies from 0 to 50 eV revealed the presence of four resonances with peaks located at 2.56 eV (π), 3.82 eV (π), 4.70 eV (σ), and between 8.30 and 9.50 eV (σ*) positions which are in good agreement with previous assignments. Moreover, the role of the multichannel coupling effects in obtaining accurate cross sections was evaluated by comparing the present results with theoretical results recently reported in the literature and early measurements performed for elastic electron collisions with furan. Electronic excitation cross sections involving the transitions from ground state to the 1B, 1A, 1A, and 1A excited states of pyrrole driven by electron impact are presented for energies from thresholds up to 50 eV and, whenever possible, critically compared with the data available in the literature.