Using force-matched potentials to improve the accuracy of density functional tight binding for reactive conditions.

We show that force matching can be used to determine accurate empirical repulsive energies for the density functional tight binding method (DFTB) for chemical reactivity in condensed phases. Our approach yields improved results over previous parametrizations for molten liquid carbon and a phenolic polymer under combustion conditions. The method we present here allows for predictions of chemical properties over longer time periods than accessible via Kohn-Sham density functional theory while retaining its accuracy.