Ab initio approach to the multichannel quantum defect calculation of the electronic autoionisation in the Hopfield series of N₂

Abstract

The two-step formulation of the multichannel quantum defect theory, applied to molecular electronic autoionistion by Giusti-Suzor (1980) and Lefebvre-Brion (1973) is used to calculate the total and partial photoionisation cross sections in the region of the Hopfield series on N2, the 700-730 AA wavelength range. The electronic quantities necessary for this treatment are obtained from ab initio calculations. The cross sections and the photoelectron angular distribution parameters are in satisfying agreement with experiment. The results clearly show that the absorption series correspond to the (B2 Sigma u+)nd sigma g series and the apparent emission series to the (B2 Sigma u+)nd pi g series.