Transferability of self-energy correction in tight-binding basis constructed from first principles.

Area of Science:

• Computational Materials Science
• Condensed Matter Physics
• Quantum Chemistry

Background:

• Accurate calculation of electronic properties requires self-energy correction (SEC).
• Calculating SEC for large systems using Kohn-Sham (KS) states is computationally expensive.

Purpose of the Study:

• To demonstrate the transferability of SEC from smaller to larger systems.
• To develop a computationally inexpensive method for estimating SEC in large systems.

Main Methods:

• Localized orbitals constructed from KS states were used to map SEC.
• A self-energy corrected Tight-Binding (TB) framework was developed.
• The scheme was applied to insulating, semiconducting, and magnetic nanoribbons of graphene and hexagonal boron nitride.

Main Results:

• SEC mapping of TB parameters was found to be transferable between systems of similar morphology.
• SEC strengthens individual π bonds and promotes charge transfer from edge to bulk in nanoribbons.
• In magnetic bipartite systems, SEC enhances inter-sublattice spin separation.

Conclusions:

• The proposed scheme enables accurate and computationally inexpensive estimation of SEC for large systems.
• This method avoids the need for explicit, expensive SEC calculations of KS single particle levels.
• The findings promise to facilitate the accurate prediction of bandgaps in large material systems.