ELECTRONIC PHASE TRANSITIONS OF CERIUM METAL.

The model recently proposed by Ram\'{\i}rez and Falicov is generalized by the incorporation of the spin-orbit splitting of the $4f$ shell. This generalization provides an understanding of the fractional valence and magnetic susceptibility of $\ensuremath{\alpha}$-cerium and suggests a mechanism to drive the $\ensuremath{\alpha}\ensuremath{-}{\ensuremath{\alpha}}^{\ensuremath{'}}$ phase transition.