We have developed a new code of the Venus atmospheric chemistry based on our photochemical model already in use for Mars (e.g., Lefèvre et al., J. Geophys. Res., 2004). For Venus, the code also includes a parameterized treatment of cloud microphysics that computes the size distribution and composition of sulphuric acid droplets. Recently, we coupled this photochemical-microphysical package to the LMD general circulation model (Lebonnois et al., J. Geophys. Res., 2010). We will describe preliminary results obtained with this first three-dimensional model of the Venus photochemistry. The distribution of key chemical species as well as their variations in space and time will be compared to observations performed from Venus Express and from the Earth.
