RYDBERG ABSORPTION SERIES OF CO2 CONVERGING TO THE 2Πu STATE OF

Abstract

The absorption spectrum of CO2 has been reinvestigated in the region 670–790 Å with a 6.8-meter grazing-incidence-type vacuum spectrograph. The Henning Rydberg series has been remeasured accurately along with its ν′ = 1 vibration series. In this manner, the ionization energy of the 2σu electron was determined to be 18.076 ev. Sixteen other Rydberg series were observed in this region. It was concluded that they are formed by the excitation of the 1πu electron. The ionization potentials corresponding to the energies of the 2Πu,3/2 and 2Πu,1/2 states of [Formula: see text] were found to be 17.312 ev and 17.323 ev respectively.