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Wannier-functions characterization of floating bonds in a-Si

M. Fornari·N. Marzari·M. Peressi·A. Baldereschi
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Abstract

We investigate the electronic structure of over-coordinated defects in amorphous silicon via density-functional total-energy calculations, with the aim of understanding the relationship between topological and electronic properties on a microscopic scale. Maximally-localized Wannier functions are computed in order to characterize the bonding and the electronic properties of these defects. The five-fold coordination defects give rise to delocalized states extending over several nearest neighbors, and therefore to very polarizable bonds and anomalously high Born effective charges for the defective atoms.

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M. Fornari, N. Marzari, M. Peressi, A. Baldereschi. 1999-11-30. Wannier-functions characterization of floating bonds in a-Si. https://arxiv.org/abs/cond-mat/9911485

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