Simple and Efficient Route toward Improved Energetics within the Framework of Density-Corrected Density Functional Theory

The crucial step in density-corrected Hartree-Fockdensityfunctional theory (DC(HF)-DFT) is to decide whether the density producedby the density functional for a specific calculation is erroneousand, hence, should be replaced by, in this case, the HF density. Weintroduce an indicator, based on the difference in noninteractingkinetic energies between DFT and HF calculations, to determine whenthe HF density is the better option. Our kinetic energy indicatordirectly compares the self-consistent density of the analyzed functionalwith the HF density, is size-intensive, reliable, and most importantlyhighly efficient. Moreover, we present a procedure that makes bestuse of the computed quantities necessary for DC(HF)-DFT by additionallyevaluating a related hybrid functional and, in that way, not onlycorrects the density but also the functional itself;we call that procedure corrected Hartree-Fock density functionaltheory (C(HF)-DFT).

Automated summary

The crucial step in DC(HF)-DFT is to determine whether the density produced by the density functional is erroneous and should be replaced by the HF density. An indicator, based on the difference in noninteracting kinetic energies between DFT and HF calculations, is introduced to make this decision. The kinetic energy indicator directly compares the self-consistent density of the analyzed functional with the HF density, and it is size-intensive, reliable, and highly efficient. Additionally, a procedure called C(HF)-DFT is presented, which not only corrects the density but also the functional itself by evaluating a related hybrid functional.