The CO₂ molecule has strong absorption lines in the neighborhood of λ = 10 µm. Assuming that the cross sections of CO₂ molecules with N₂ and O₂ molecules are σ(CO₂, N₂) = 1.20 nm² and σ(CO₂, O₂) = 0.95 nm², estimate the collision- broadened linewidth for CO₂ in the atmosphere. (Note: Since the concentration of CO₂ is very small compared to N₂ and O₂ in air, you may assume that only N₂-CO₂ and O₂-CO2 collisions contribute to the linewidth.) Compare this to the Doppler width.

The CO₂ molecule has strong absorption lines in the neighborhood of λ = 10 µm. Assuming that the cross sections of CO₂ molecules with N₂ and O₂ molecules are σ(CO₂, N₂) = 1.20 nm² and σ(CO₂, O₂) = 0.95 nm², estimate the collision- broadened linewidth for CO₂ in the atmosphere. (Note: Since the concentration of CO₂ is very small compared to N₂ and O₂ in air, you may assume that only N₂-CO₂ and O₂-CO2 collisions contribute to the linewidth.) Compare this to the Doppler width.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 6P

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