The atmosphere of hot Jupiters can be probed by primary transit andsecondary eclipse spectroscopy. In order to constrain the atmospheric thermalstructure and composition from observables, chemical models are necessary. Dueto the intense UV irradiation, mixing and circulation, the chemical composition ismaintained out of equilibrium and kinetic photochemical models must be appliedwith kinetics valid at the high temperatures prevailing in hot Jupiters atmospheres.We study the steady state atmospheric composition of HD 189733b one of themost observed hot Jupiters by implementing a new kinetic network in a 1D time-dependent chemical model including photodissociations and vertical diffusion. Weconfirm that the atmospheric composition of the planet is maintained out of theequilibrium by photodissociations and vertical quenching. The core and noveltyof this study is the chemical scheme. It was produced in close collaboration withexperts of applied high-temperature kinetics and methodically validated over arange of temperatures and pressures typical of the atmospheric layers influencingthe observations of hot Jupiters. In addition to our nominal chemical scheme, weimplemented other reaction sub-networksfor nitrogen-bearing species that are commonly used in the field of combustion, and investigate the sensitivity of thepredicted abundances and spectra to the network. We found that the abundances ofNH3and HCN can vary by 2 orders of magnitude. A spectral feature of NH3at10.5μm is sensitive to these abundance variations and thus to the chemical scheme.< Leer menos