Convex envelope
= Convex envelope
{title2=$\operatorname{co}f$}
The greatest <convex function> lying below a given function, when such an envelope is considered in the specified domain. A <convex combination> of phase compositions and their <Gibbs free energies> constructs candidate mixtures; the equilibrium free energy is their lower <convex envelope>. For two differentiable coexisting branches, the supporting line is a <common tangent>.