Maximally-localised Wannier functions as building blocks of  electronic structure

We combine large-scale, ab initio electronic structure calculations and the maximally-localised Wannier function (MLWF) approach in order to study the electronic properties of complex nanostructures. MLWFs provide an  accurate, localised, minimal basis set in which to diagonalise the Hamiltonian. In the MLWF basis, Hamiltonians for large, complex systems can be constructed directly from the short-ranged Hamiltonians of smaller constituent units by performing full first-principles calculations on either periodically-repeated or isolated fragments. We apply our approach to the case of DNA helices. This work has led to the development of a new   open-source code called Wannier90 [1] and opens the way to obtaining a more detailed understanding of charge transport and conductance in DNA, bringing closer the prospect of engineering its electronic structure for use in nano-electronic circuits and biotechnology applications.

[1] A.A. Mostofi et al., Wannier90: A tool for obtaining maximally-localized Wannier functions, http://arxiv.org/abs/0708.0650, http://www.wannier.org