Generalized Optimized Effective Potential for Orbital Functionals and Self-Consistent Calculation of Random Phase...

Area of Science:

• Quantum Chemistry
• Computational Physics
• Materials Science

Background:

• Orbital-dependent density functional approximations (DFAs) are crucial for accurate electronic structure calculations.
• Traditional methods often struggle with describing weakly interacting systems like van der Waals complexes.
• Self-consistent calculations are essential for refining the accuracy of theoretical models.

Purpose of the Study:

• To introduce a novel self-consistent procedure for calculating total energy using orbital-dependent DFAs.
• To develop and validate the generalized optimized effective potential (GOEP) method.
• To enhance the description of van der Waals interactions in computational chemistry.

Main Methods:

• Development of the generalized optimized effective potential (GOEP) as a nonlocal Hermitian potential.
• Implementation of GOEP for self-consistent calculations of random phase approximation (RPA) correlation functionals.
• Application to particle-hole (ph) and particle-particle (pp) channels.

Main Results:

• The GOEP method successfully minimizes total energy, yielding consistent occupied and virtual orbitals.
• Self-consistent RPA calculations using GOEP significantly improve the accuracy for van der Waals systems.
• GOEP captures essential single excitation contributions, leading to orbital renormalization without explicit inclusion in the energy functional.

Conclusions:

• The GOEP procedure offers a promising and effective optimization approach for orbital-dependent functionals.
• This method provides a pathway to more accurate predictions of weakly interacting systems.
• GOEP enables self-consistent treatment of electronic excitations, advancing computational quantum chemistry.