Increase of Radiative Forcing through Midinfrared Absorption by Stable CO₂ Dimers?

ABSTRACT: We performed matrix-isolation infrared (MI-IR) spectroscopy of carbon dioxide monomers, CO₂, and dimers, (CO₂)₂, trapped in neon and in air. On the basis of vibration configuration interaction (VCI) calculations accounting for mode coupling and anharmonicity, we identify additional infrared-active bands in the MI-IR spectra due to the (CO₂)₂ dimer. These bands are satellite bands next to the established CO₂ monomer bands, which appear in the infrared window of Earth's atmosphere at around 4 and 15 μm. In a systematic carbon dioxide mixing ratio study using neon matrixes, we observe a significant fraction of the dimer at mixing ratios above 300 ppm, with a steep increase up to 1000 ppm. In neon matrix, the dimer increases the

SUBMITTER: Dinu DF 

PROVIDER: S-EPMC9125687 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature