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arXiv · 2008.04642

Analytical Approach to Phonon Calculations in the SCC-DFTB Framework

Vladimir Bacic·Thomas Heine·Agnieszka Kuc
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Abstract

Detailed derivation of the analytical, reciprocal-space approach of Hessian calculation within the self-consistent-charge density functional based tight-binding framework (SCC-DFTB) is presented. This approach provides an accurate and efficient way for obtaining the SCC-DFTB Hessian of periodic systems. Its superiority with respect to the traditional numerical force differentiation method is demonstrated for doped graphene, graphene nanoribbons, boron-nitride nanotubes, bulk zinc-oxide and other systems.

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Vladimir Bacic, Thomas Heine, Agnieszka Kuc. 2020-08-11. Analytical Approach to Phonon Calculations in the SCC-DFTB Framework. https://doi.org/10.1063/5.0023666

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