On the Rathenau bands in the absorption spectrum of CO2

✍ Scribed by H.-J. Werner; A. Spielfiedel; N. Feautrier; G. Chambaud; P. Rosmus

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 577 KB
• Volume: 175
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(90)85543-l

✦ Synopsis

High-accuracy multireference configuration interaction calculations for the energies of the lowest two singlet and triplet I'I, states of CO* as a function of the symmetric stretching coordinate are reported. It has been found that these IT, states have ionic cores corresponding to the X 'Q and A 211U states of CO,+ _ They lie close in energy and form an avoided crossing along the symmetric stretching coordinate. Due to this avoided crossing the lowest %, state exhibits a double minimum in Dmh symmetry.

Our results imply that most of the spectral features in the absorption spectrum of CO1 lying between I 1.4 and 12.6 eV known as the Rathenau bands originate from the lowest two vibronically coupled II. states.