Adaptability and accuracy of all-electron pseudopotentials

We suggest several ways of improving pseudopotential transferability within the approach based on all-electron self-consistent pseudopotentials. Particularly, we show that the pseudopotentials constructed for two energy channels and using the pseudized core charge included in exchange and correlation potential terms, can provide an exact and stable solution for cases where the current pseudopotential methods encounter difficulties and need special treatment. Examples such as semicore states participating in the chemical bond, extended valence states, or a significant charge transfer in alkali chlorides are presented. The need for the semiempirical choice of “suitable” atomic configuration in the pseudopotential generating process is eliminated and also the higher l-pseudopotential components are generated in a natural way. Also some general aspects of pseudopotential transferability are discussed in detail.