  This article reviews a method for calculating an equilibrium interfacial
phase diagram depicting regions of stability for different interface structures
as function of temperature and chemical potentials. Density functional theory
(DFT) is used for interfacial energies, Monte Carlo simulations together with
cluster expansions based on DFT results for obtaining configurational free
energies, and CALPHAD-type modeling for describing the thermodynamic properties
of the adjoining bulk phases. An explicit case, vanadium doped cemented
carbides, is chosen to illustrate the progress in the research field and the
interfacial diagram, a complexion diagram, for the phase boundary WC(0001)/Co
is constructed as function of temperature and chemical potentials.
