Exact Coulomb cutoff technique for supercell calculations

Screened Coulomb interactions in metallic alloys. I. Universal screening in the atomic-sphere approximation

We have used the locally self-consistent Green’s function (LSGF) method in supercell calculations to establish the distribution of the net charges assigned to the atomic spheres of the alloy components in metallic alloys with different compositions and degrees of order. This allows us to determine the Madelung potential energy of a random alloy in the single-site mean field approximation which ...

Charged point defects in semiconductors and the supercell approximation

The effects of the supercell approximation in first-principles calculations for isolated, charged point defects in semiconductors and insulators are studied. The convergence of the Coulomb energy with respect to the supercell size is investigated. Quantitative numerical results for the standard uniform compensating charge and the newly proposed localized compensating charge scheme are presented...

Supercell program: a combinatorial structure-generation approach for the local-level modeling of atomic substitutions and partial occupancies in crystals

BACKGROUND Disordered compounds are crucially important for fundamental science and industrial applications. Yet most available methods to explore solid-state material properties require ideal periodicity, which, strictly speaking, does not exist in this type of materials. The supercell approximation is a way to imply periodicity to disordered systems while preserving "disordered" properties at...

Ab initio evaluation of Coulomb and exchange parameters for DFT+U calculations

Conventional density functional theory DFT fails for materials with strongly correlated electrons, such as late transition metal oxides. Large errors in the intra-atomic Coulomb and exchange interactions are the source of this failure. The DFT+U method has provided a means, through empirical parameters, to correct these errors. Here, we present a systematic ab initio approach in evaluating the ...

Ewald Summation for Coulomb Interactions in a Periodic Supercell