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Theory of composite-band Wannier states and order-N electronic-structure calculations

Takeo Hoshi·Takeo Fujiwara
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Abstract

From the order-N electronic-structure formulation, a Hamiltonian is derived, of which lowest eigen state is the generalized or composite-band Wannier state. This Hamiltonian maps the locality of the Wannier state to that of a virtual impurity state and to a perturbation from a bonding orbital. These theories are demonstrated in the diamond-structure solids, where the Wannier states are constructed by a practical order-N algorithm with the Hamiltonian. The results give a prototypical picture of the Wannier states in covalent-bonded systems.

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Takeo Hoshi, Takeo Fujiwara. 2000-08-16. Theory of composite-band Wannier states and order-N electronic-structure calculations. https://doi.org/10.1143/jpsj.69.3773

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