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arXiv · 1111.2022

Range separated functionals in the density functional based tight binding method: Formalism

Thomas A. Niehaus·Fabio Della Sala
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Abstract

A generalization of the density-functional based tight-binding method (DFTB) for the use with range-separated exchange-correlation functionals is presented. It is based on the Generalized Kohn-Sham (GKS) formalism and employs the density matrix as basic variable in the expansion of the energy functional, in contrast to the traditional DFTB scheme. The GKS-TB equations are derived and appropriate integral approximations are discussed in detail. Implementation issues and numerical aspects of the new scheme are also covered.

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Thomas A. Niehaus, Fabio Della Sala. 2011-11-08. Range separated functionals in the density functional based tight binding method: Formalism. https://doi.org/10.1002/pssb.201100694

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