| “Tight binding” has existed for many years as a convenient and transparent model for the
description of electronic structure in molecules and solids. It often provides the basis for
construction of many body theories such as the Hubbard model and the Anderson impurity
model. Slater and Koster call it the tight binding or “Bloch” method and their historic
paper provides the systematic procedure for formulating a tight binding model.1 In their
paper you will find the famous “Slater–Koster” table that is used to build a tight binding
hamiltonian. This can also be found reproduced as table 20–1 in Harrison’s book and
this reference is probably the best starting point for learning the tight binding method.2
Building a tight binding hamiltonian yourself, by hand, as in Harrison’s sections 3–C and
19–C is certainly the surest way to learn and understand the method. The rewards are very
great, as I shall attempt to persuade you now. More recent books are the ones by Sutton,3
Pettifor4 and Finnis.5 In my development here I will most closely follow Finnis. This is
because whereas in the earlier literature tight binding was regarded as a simple empirical
scheme for the construction of hamiltonians by placing “atomic-like orbitals” at atomic
sites and allowing electrons to hop between these through the mediation of “hopping inte-
grals,” it was later realised that the tight binding approximation may be directly deduced as
a rigorous approximation to the density functional theory. This latter discovery has come
about largely through the work of Sutton et al.6 and Foulkes;7 and it is this approach that
is adopted in Finnis’ book from the outset.
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