Comments on the basis spinors in Dirac-Fock-Roothaan calculations

Abstract

It is noted that two kinds of basis spinors (the unified and the separated basis spinors) employed in Dirac-Fock-Roothaan calculations are equivalent. For large components of the basis spinors the separated basis spinors take simpler forms than the unified ones while for small components the reverse is true when the kinetic energy balance scheme is adopted.