Scalar relativistic all-electron density functional calculations on periodic systems

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Materials Science

Background:

• Scalar relativistic effects are crucial for accurate electronic structure calculations, especially for heavy elements.
• Previous methods often struggled to include these effects consistently for all electrons.

Purpose of the Study:

• To implement and validate a method for relativistic all-electron calculations using Gaussian orbitals.
• To apply this method to Density Functional Theory (DFT) approximations.

Main Methods:

• Incorporation of scalar relativistic effects within periodic boundary conditions using Gaussian orbitals.
• Utilizing the third-order Douglas-Kroll-Hess approximation.
• Application to local spin-density, generalized gradient approximation (GGA), meta-GGA, and hybrid functionals.

Main Results:

• Successful benchmark calculations for bulk metals (Pd, Ag, Pt, Au).
• Accurate results for large band gap semiconductors (AgF, AgCl).
• Demonstrated the capability of treating all electrons on an equal footing.

Conclusions:

• The developed methodology provides a robust framework for relativistic all-electron DFT calculations.
• This approach enhances the accuracy of electronic structure predictions for systems with significant relativistic contributions.
• The study validates the method's performance across various metallic and semiconducting materials.