Identification of the (CO2)2 Dimer Vibrations in the ν1, 2ν2 Region: Anharmonic Variational Calculations

✍ Scribed by A.A Vigasin; F Huisken; A.I Pavlyuchko; L Ramonat; E.G Tarakanova

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 114 KB
• Volume: 209
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2001.8409

✦ Synopsis

This paper aims at examination of the (CO 2 ) 2 spectral absorption profile retrieved from the room temperature CO 2 collisioninduced absorption (CIA) spectrum in the region of the ν 1 , 2ν 2 Fermi doublet. The assignment of (CO 2 ) 2 vibrations is discussed, paying due attention to high-resolution CARS observations in the regions of ν low and ν up . A variational solution of the anharmonic vibrational problem for the (CO 2 ) 2 dimer was obtained using an extended basis set consisting of harmonic and Morse oscillator wave functions. This allowed for a satisfactory description of the vibrational dimer ν 1 , 2ν 2 spectrum from first principles. In particular, we have succeeded in proving that the diffuse absorption band seen in the trough between the major Fermi-coupled CIA bands belongs to combinations of CO 2 bending vibrations in a dimer.