NON-SELF-CONSISTENT FIRST-PRINCIPLES CALCULATIONS FOR TOTAL-ENERGY DIFFERENCES

We assess the accuracy of two non-self-consistent first-principles cal culations. The first one is the accuracy of frozen-potential approxima tion which may be useful for the study of phase diagrams of alloys. Se condly, we show that the structural properties obtained by the self-co nsistent calculations based on the generalized-gradient approximation (GGA) are accurately reproduced by the non-self-consistent calculation s with the GGA functional, using the electron density obtained by the local-spin-density approximation. (C) 1998 Elsevier Science B.V. All r ights reserved.