Influence of an improved local-spin-density correlation-energy functional on the cohesive energy of alkali metals

The new, accurate, correlation energy of the spin-polarized homogeneous electron gas due to Vosko, Wilk, and Nusair, based on the "exact" Monte Carlo calculations of Ceperley and Alder, is used to evaluate the cohesive energies of the alkali metals Li, Na, K, and Rb. The new cohesive energies for Li, Na, K, and Rb are 129, 90, 72, and 57 mRy, which differ from experiment by +7, +7, +3, and -7 mRy, respectively, and are approximately 8 mRy larger than those obtained by Janak, Moruzzi, and Williams. Of particular note is the significant improvement in the agreement between theory and experiment for Rb.