Electric quadrupole transitions in carbon dioxide

Recent advances in high sensitivity spectroscopy have made it possible, combination with accurate theoretical predictions, to observe, for the first time, very weak electric quadrupole transitions a polar polyatomic molecule of water. Here, we present predictions complete rovibrational spectrum non-polar CO2, important atmospheric and astrophysical applications. Our are validated by recent cavity enhanced absorption measurements used assign few features ExoMars Atmospheric Chemistry Suite mid-infrared spectroscopic observations Martian atmosphere. Predicted appear some CO2 water vapor transparency regions, making them detection characterization minor absorbers water- CO2-rich environments, such as those atmospheres Earth, Venus, Mars.