ABSTRACT The Green function of a tight-binding model with mixed impurities is calculated exactly. The spectral properties of the one-dimensional lattice, including both extended and localized states, are also analysed exactly. The authors... more
ABSTRACT The Green function of a tight-binding model with mixed impurities is calculated exactly. The spectral properties of the one-dimensional lattice, including both extended and localized states, are also analysed exactly. The authors find at most two localized states which are always non-degenerate. The density of states per site in the continuum is calculated. Using a constructive procedure they obtain the localized eigenfunctions for the infinite and semi-infinite chain. Some results for three-dimensional lattices are presented.
