Brillouin-zone integration by Fourier quadrature: Special points for superlattice and supercell calculations

A simple extension of the Monkhorst-Pack Fourier-quadrature (or special-points) method for Brillouin-zone integration makes it possible to determine equivalent (identical by symmetry) points for two different unit cells simply by identifying lattice points common to both cells. This is useful for superlattice or supercell geometries in order to minimize systematic errors.