The traditional van der Waals theory provides a mean-field approximation of phase behavior for liquid-gas coexistence in the thermodynamic limit as N → ∞ and V → ∞, while maintaining a constant density ρ = N V . Beyond the mean-field approximation, realistic finite systems exhibit richer microscopic details due to interfacial effects. Below the critical temperature, the liquid-gas coexistence phase exhibits intricate microscopic structures, such as spherical droplets or cylindrical liquid regions. at low concentrations while cylinders, as well as other periodic morphologies, are formed only at higher densities.