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arXiv · 2109.10416

Improving the Silicon Interactions of GFN-xTB

Leonid Komissarov·Toon Verstraelen
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Abstract

A general-purpose Density Functional Tight Binding method, the GFN-xTB model is gaining increased popularity in accurate simulations that are out of scope for conventional ab initio formalisms. We show that in its original GFN1-xTB parametrization, organosilicon compounds are described poorly. This issue is addressed by re-fitting the model's silicon parameters to a data set of ten thousand reference compounds, geometry-optimized with the revPBE functional. The resulting GFN1-xTB-Si parametrization shows improved accuracy in the prediction of system energies, nuclear forces and geometries and should be considered for all applications of the GFN-xTB Hamiltonian to systems that contain silicon.

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Leonid Komissarov, Toon Verstraelen. 2021-09-21. Improving the Silicon Interactions of GFN-xTB. https://doi.org/10.1021/acs.jcim.1c01170

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