DFTB Parameters for the Periodic Table: Part III, Spin-Orbit Coupling.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Computational Chemistry

Background:

• Spin-orbit coupling (SOC) is essential for accurately describing electronic structure, transport properties, and topological phenomena in inorganic semiconductors.
• Existing methods may lack comprehensive SOC parameterization for broad material applications.

Purpose of the Study:

• To develop a consistent and reliable set of SOC parameters for the density-functional based tight-binding (DFTB) method.
• To extend the applicability of DFTB to systems where SOC effects are significant.

Main Methods:

• Calculated atomic SOC data using density-functional theory (DFT).
• Developed and validated a comprehensive set of SOC parameters for the DFTB method across the periodic table.
• Tested the parameters on diverse systems including transition metal dichalcogenides, III-V semiconductors, and topological insulators.

Main Results:

• A consistent set of SOC parameters for the DFTB method was established.
• The parameters accurately reproduced electronic and topological properties in tested systems.
• Demonstrated the utility of the parameterization for complex material structures.

Conclusions:

• The new DFTB SOC parameters provide a robust tool for electronic structure and transport calculations.
• This work facilitates the study of large and complex systems, such as twisted van der Waals heterostructures.
• Enables advanced computational investigations of materials with significant spin-orbit coupling effects.