Variational cellular model of the energy bands of silicon

The recently proposed variational cellular method is formulated for application to three‐dimensional periodic structures with an arbitrary number of atoms per unit cell. The method is used here to determine the electronic structure of silicon. The energy band calculations were carried out with the unit cell partitioned into four space‐filling polyhedra. Interstitial cells were included in order to improve on the spherical cellular potentials. The calculations reported show that the method requires a small computational effort to obtain accurate and well‐converged results.