Vertical variations of mole fractions (denoted x_i) of the main components (i.e., N₂, C₂ H₆ and CH₄) of Titan’s alkanofer liquid. This figure depicts a scenario where the icy crust is assumed to be isothermal at the temperature T₀ = 90 K. The pressurevaries between 1.5 bar at the surface (z = 0) and around 130 bar at the bottom of the simulated system (depth of z = 10 km). The three panels correspond to different surface compositions, expressed in mole fractions: (a) N₂: 0.05, C₂ H₆: 0.20, CH₄: 0.75; (b) N₂: 0.20, C₂ H₆: 0.20, CH₄: 0.60; (c) N₂: 0.20, C₂ H₆: 0.30, CH₄: 0.50. For all computations, the porosity of the water ice matrix was fixed to 5%, the diffusion theory formalism follows Ghorayeb & Firoozabadi (2000), the water ice equation of state was provided by Feistel & Wagner (2006), while the thermodynamic properties of liquids were computed using PC-SAFT.