A range-separated generalized Kohn-Sham method including a long-range nonlocal random phase approximation correlation...

Area of Science:

• Quantum Chemistry
• Computational Materials Science
• Theoretical Chemistry

Background:

• Density-functional theory (DFT) methods are crucial for electronic structure calculations.
• Random Phase Approximation (RPA) offers a promising route to accurate correlation energies.
• Existing range-separated RPA methods have limitations in variational treatment.

Purpose of the Study:

• Introduce a novel, fully variational generalized Kohn-Sham (GKS) method.
• Incorporate a long-range nonlocal RPA correlation potential into orbital optimization.
• Enhance the accuracy of electronic structure calculations for various chemical systems.

Main Methods:

• Developed a self-consistent minimization approach with respect to the one-particle density matrix.
• Implemented a range-separated RPA functional within a variational GKS framework.
• Benchmarked the new method against existing RPA schemes and G0W0 calculations.

Main Results:

• The new variational GKS-RPA method significantly improves upon standard RPA and post-GKS RPA.
• It demonstrates superior performance for main group thermochemistry, kinetics, and noncovalent interactions.
• Outperforms the G0W0 method in predicting ionization potentials and fundamental gaps.

Conclusions:

• The developed variational GKS-RPA method represents a significant advancement in electronic structure theory.
• It offers a more accurate and robust approach for a wide range of chemical applications.
• Provides a powerful alternative to G0W0 for calculating electronic properties.