Implementation of density functional embedding theory within the projector-augmented-wave method and applications to...

Area of Science:

• Computational Materials Science
• Quantum Chemistry
• Solid-State Physics

Background:

• Density Functional Theory (DFT) is a powerful tool for electronic structure calculations.
• Accurately modeling defects in semiconductors often requires computationally expensive methods.
• Existing embedding methods have limitations in efficiency and applicability.

Purpose of the Study:

• To implement and validate a new Density Functional Embedding Theory (DFET) within the VASP code.
• To demonstrate the capability of DFET for studying point defects in semiconductors.
• To leverage the full features of VASP, including the projector-augmented-wave (PAW) formalism, for DFET.

Main Methods:

• Developed new algorithms for optimized effective potential (OEP) optimization within the PAW formalism.
• Integrated DFET into the VASP code, utilizing its PAW library and various DFT functionals.
• Tested the implementation on diverse systems: molecules, metal surfaces, and bulk semiconductors.

Main Results:

• The new DFET implementation generates robust and physically correct embedding potentials.
• Embedded cluster models using DFET accurately reproduce the electronic structure of point defects in semiconductors.
• The method shows robustness across different basis sets (plane-wave and Gaussian-type orbitals).

Conclusions:

• DFET is validated as a reliable method for studying semiconductor point defects.
• The VASP-based DFET implementation offers enhanced computational efficiency and flexibility.
• DFET presents a promising accurate and efficient approach for investigating isolated defects in materials.