Extended DFT + U + V method with on-site and inter-site electronic interactions.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Computational Chemistry

Background:

• The DFT+U method is widely used for electronic structure calculations but has limitations for systems with significant electron delocalization.
• Accurately modeling electronic interactions, including on-site and inter-site effects, is crucial for understanding material properties.
• Mott localization and orbital hybridization are key phenomena in many advanced materials.

Purpose of the Study:

• To introduce a generalized DFT+U method based on the extended Hubbard model.
• To develop a corrective Hamiltonian capable of studying systems with delocalized electrons and inter-site hybridization.
• To provide a unifying and accurate computational approach for diverse electronic systems.

Main Methods:

• Generalization of the DFT+U method.
• Incorporation of on-site and inter-site electronic interactions via an extended Hubbard model.
• Development of a novel corrective Hamiltonian.

Main Results:

• The extended functional accurately describes Mott-charge-transfer insulators like NiO.
• The method demonstrates accuracy for covalently bonded insulators such as Si and GaAs.
• The approach offers a versatile and unifying description for a wide range of materials.

Conclusions:

• The generalized DFT+U method provides an accurate and versatile tool for electronic structure calculations.
• This novel approach successfully captures complex electronic interactions beyond the standard DFT+U.
• The method paves the way for more reliable predictions of material properties across diverse systems.