Collisional excitation of CO2 by He : New potential energy surface and scattering calculations
Résumé
The CO2-He collisional system is suited for benchmarking new experimental and theoretical methods. Thus, it was well studied during the last decades.
In this talk, I will present our new study of the CO2-He collisional system. A new potential energy surface was calculated at the coupled cluster level of theory with a complete basis set extrapolation. The potential energy surface accuracy was tested through the comparison of bound states and pressure broadening coefficients with experimental data.
Finally, revised collisional rate coeffcients were provided in the 10 - 300 K temperature range. Such data can also be used for the interpretation of astrophysical observations in media where both CO2 and He species are abundant. We expect that these new collisional data will stimulate new experimental studies at low or room temperature.