Ionization spectrum of CO2 studied by the SAC-CI general-R method

The SAC-CI (symmetry-adapted-cluster configuration-interaction) general-R m ethod was used to assign the satellite peaks of the ionization spectrum of CO2. Outer-valence satellite peaks were assigned to the (IIu)-I-2 and (IIg) -I-2 states and inner-valence satellite peaks were assigned to the (2)Sigma (u)(+) and (2)Sigma(g)(+) states. The SAC-CI general-R method reproduces we ll the experimental spectrum in both the outer and inner-valence regions. O n the other hand, while the SAC-CI SD-R method calculates the main peaks qu ite well, the shake-up states are by about 3 eV higher than those of the ge neral-R method. (C) 1999 Elsevier Science B.V. All rights reserved.