  We developed a 1D photo-thermochemical model to study the atmosphere of warm
exoplanets. The chemical scheme used in this model is completely new in
planetology and has been constructed in collaboration with specialists of
combustion. It has been validated as a whole through experiments on a large
range of temperature (300 - 2500 K) and pressure (1 mbar - 100 bar), allowing
to study a wide variety of exoplanets. We have used this chemical model to
study the atmosphere of two warm Neptunes, GJ3470b and GJ436b, and the
influence of different parameters (vertical mixing, metallicity, temperature, .
. . ) on their chemical composition. We present here the results obtained in
these studies.

Earth and Planetary Astrophysics