SELF-INTERACTION-CORRECTED DENSITY-FUNCTIONAL FORMALISM

In recent years the self-interaction-corrected (SIC) density-functional formalism has been applied to many physical systems. We discuss the Kohn-Sham-like SIC equations within the framework of the density-functional theory. We prove that in the SIC method the kinetic energy of the noninteracting electron gas T-0[n(up arrow), n(down arrow)] is evaluated erroneously. Since the kinetic energy is, in general, a large part of the total energy, this fact represents a crude approximation in the method and may lead to appreciable errors in the final results.