Contact parameter values calculated from the laboratory measurements of critical saturation as a function of temperature for C₆H₆ nucleation onto tholins (black points and error bars) and a linear fit (purple line). Shown in red are the contact parameters and linear fit to the measurements of benzene nucleation on a silicon substrate. The green dashed line shows the temperature-independent contact parameter used for the benzene study in D. Dubois et al. (2021).