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Parameterization of tight-binding models from density functional theory calculations
We present a rigorous bottom-up approach for the derivation of the electronic structure part of tight-binding (TB) models from density functional theory (DFT) calculations. The approach is based on a simultaneous optimization and projection of atomic-like orbitals on self-consistent DFT wave functions and is universally applicable to elements and compounds in arbitrary structural arrangements. The quality and transferability of the derived TB bond and overlap integrals are demonstrated for the examples of a covalent semiconductor (carbon), a transition metal (titanium), and a binary compound with mixed metallic-covalent bonding (TiC). The method can serve as a transparent and physically justified coarse-graining scheme for the construction of nonorthogonal and orthogonal TB total-energy models as well as the closely related bond-order potentials.