KRR-ASA METHOD IN EXACT EXCHANGE-POTENTIAL BAND-STRUCTURE CALCULATIONS

We present a method of electronic band-structure calculation which inc orporates the exact Kohn-Sham density-functional exchange (EXX) potent ial approach with the Korringa-Kohn-Rostoker (KKR) method in the atomi c-sphere approximation (ASA). It takes full account of the energy depe ndence of the radial functions, and hence, provides more accurate trea tment in principle than our previous one based on the linearized muffi n-tin orbital method [Phys. Rev. Lett. 74, 2989 (1995)]. In this metho d, we treat C, Si, Ge, MgO, CaO, and MnO (Antiferrro-II), which were p reviously studied in the framework of the linear-muffin-tin orbital me thod with EXX. The results are basically in agreement with the old one s, though small differences produce non-negligible effects on the resu lts. Some numerical paints as well as the strict formulation of KKK in the ASA are discussed.