Matrix isolation spectra of the carbon dioxide monomer and dimer revisited

New FTIR CO2 high resolution spectra are recorded in argon and nitrogen matrices at 11 K at high dilution. Their evolution with CO2 diffusion at higher temperature is also traced. New observations are discussed in regard to previous works. Even at high dilution (1/10 000), the temperature increase causes appearance of several bands both in argon and nitrogen. Identification of carbon dioxide dimer absorptions is tentatively proposed, (C) 2000 Elsevier Science B.V. All rights reserved.