Abstract
The cohesive energies of the light actinide metals have been calculated from first principles using the density functional formalism and self-consistent RLMTO energy band calculations. The band contribution to cohesion increases across the series but the contribution from free-atom preparation energies increases more rapidly, resulting in cohesive energies that decrease across the series. The modification of the band contribution to cohesion by spin-orbit splitting is significant in the middle of the series.