Experimental measurements of collision-induced absorption (CIA) cross-sections for CO2-H2 and CO2-CH4 complexes were performed using Fourier transform spectroscopy over a spectral range of 100-500 cm and a temperature range of 200-300 K. These experimentally derived CIA cross-sections agree with the spectral range and temperature dependence of the calculation by \citeA{Robin}, however the amplitude is half of what was predicted. Furthermore, the CIA cross-sections reported here agree with those measured by \citeA{Turbet}. The CIA cross-sections can be applied to planetary systems with CO$_{2}$-rich atmospheres, such as Mars and Venus, and will be useful to terrestrial spectroscopists. Additionally, radiative transfer calculations of the early Mars atmosphere were performed and showed that CO2$-CH4 CIA would require surface pressure greater than 3 bar for a 10% methane atmosphere to achieve 273 K at the surface. CO2-H2, however, liquid water is possible with 5% hydrogen and less than 2 bar of surface pressure.

Experimental measurements of collision-induced absorption (CIA) cross-sections for CO-H2 and CO2-CH4 complexes were performed using Fourier transform spectroscopy over a spectral range of 100-500 cm and a temperature range of 200-300 K. These experimentally derived CIA cross-sections agree with the spectral range and temperature dependence of the calculation by Wordsworth (2017), however the amplitude is half of what was predicted. Furthermore, the CIA cross-sections reported here agree with those measured by Turbet (2019). The CIA cross-sections can be applied to planetary systems with CO2-rich atmospheres, such as Mars and Venus, and will be useful to terrestrial spectroscopists. Additionally, radiative transfer calculations of the early Mars atmosphere were performed and showed that CO2-CH4 CIA would require surface pressure greater than 3 bar for a 10% methane atmosphere to achieve 273 K at the surface. CO2-H2, however, liquid water is possible with 5\% hydrogen and less than 2 bar of surface pressure.