DFTB Parameters for the Periodic Table: Part 1, Electronic Structure
Mohammad Wahiduzzaman1,2, Augusto F Oliveira1,2, Pier Philipsen2
1School of Engineering and Science, Jacobs University Bremen , Campus Ring 1, 28759 Bremen, Germany.
Abstract:
A parametrization scheme for the electronic part of the density-functional based tight-binding (DFTB) method that covers the periodic table is presented. A semiautomatic parametrization scheme has been developed that uses Kohn-Sham energies and band structure curvatures of real and fictitious homoatomic crystal structures as reference data. A confinement potential is used to tighten the Kohn-Sham orbitals, which includes two free parameters that are used to optimize the performance of the method. The method is tested on more than 100 systems and shows excellent overall performance.
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