Photoelectron spectroscopy of carbon dioxide

Abstract

Photoelectron spectra of carbon dioxide have been studied at photon wavelengths of 736, 744, 876, and 584 Å, respectively. Many previously unknown vibrational levels of the X²Π_g state of the molecular ion have been observed. Some new levels corresponding to (v₁, 0, 0) with v₁=0 to 10 and (0, 0, v₃) with v₃=2, 4, 6, 8 have been measured along with some levels of the (v₁, 0, v₃) series. Level (0, v₂, 0) with v₂=1, has been observed in the photoelectron spectrum obtained at 876 λ. The values of 1309±40, 605±60, and 1476±40 cm^-1 have been assigned to v₁, v₂, and v₃, respectively. The effect of autoionization on the vibrational intensities of the (v₁, 0, 0) states with v₁=0, 1, 2 has also been studied at 736 Å and the vibrational populations have been compared with those at 744 and 584 Å, respectively.