Optika Atmosfery i Okeana Journal

Vol. 38, issue 02, article # 1

Lavrent'ev N. A., Rodimova O. B., Fazliev A. Z. On the spectral behavior of “unidentified” continious absorption in 8800 and 10600 cm^-1 H₂O bands. // Optika Atmosfery i Okeana. 2025. V. 38. No. 02. P. 87–92. DOI: 10.15372/AOO20250201 [in Russian].
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Abstract:

The parts of the water vapor continuum absorption conditioned by different physical mechanisms are investigated. The difference between the water vapor continuum absorption calculated according to the asymptotic line wing theory and that found from experiment is the sum of absorption by stable dimers and absorption due to some other absorbing objects. This “unidentified” absorption was found for intervals centered at 8800 and 10600 cm^-1. The spectral behavior of the “unidentified” absorption turned out to be similar to that obtained in the case of modeling the continuum absorption by H₂O dimers through the equilibrium constants of the corresponding reactions. The difference in the unidentified absorption curves found by the two methods can be considered a lower limit of absorption by the monomer wings. Among the graphs available in GrafOnto information system, graphs were found that were qualitatively similar to the unidentified absorption. The results can be considered encouraging, but not final, since the system contains only a limited set of substances.

Keywords:

IR absorption, water vapor, dimers, line wings, the GrafOnto information system

Figures:

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