(DFT) calculations, as shown in Figure . The phase stability is determined by the total energies of the material of interest and its competing phases, the defect formation energy diagram is drawn from total energy calculations of possible point defects in the host material, and the carrier concentration is calculated from the density of states (DOS) of the material together with the defect formation energies. We illustrate the software usage in this section, while Section 3 provides details on the underlying theory.