Mixing ratio profiles of various neutral species in Titan’s dayside upper atmosphere including hydrocarbons (a), nitriles (b), and radicals (c and d), adapted from model results of Lavvas et al. (2008a,b) at 800−1300 km which have been updated with the improved chemical network in Titan’s atmosphere and ionosphere. These mixing ratio profiles are extrapolated to higher altitudes assuming diffusive equilibrium (indicated by the dashed lines).