抄録
An effective Hamiltonian which operates on the Bloch function consisting of atomic p-functions is constructed and solved at the points of interest in the Brillouin zone, namely at T and L. The nearest and next nearest neighbour interactions are taken into account and they are expanded to the first order of distortions of the lattice from the simple cubic structure. The eigenvalues obtained here are the same as those obtained from the ordinary tight-binding calculation. The present approach, however, not only seems mathematically more transparent than the ordinary treatment, but also the forms of the effective Hamiltonians obtained are expected to be of use when a more general effective Hamiltonian is constructed from a point of view of the symmetry of the crystals.
