Simulation of all-order density-functional perturbation theory, using the second order and the strong-correlation...

Area of Science:

• Computational chemistry
• Quantum mechanics
• Materials science

Background:

• Electronic structure calculations are crucial for predicting material properties.
• The density-functional perturbation series offers a formally exact way to construct exchange-correlation energy.
• This series often diverges for real systems, limiting its practical application.

Purpose of the Study:

• To address the divergence issue of the density-functional perturbation series.
• To develop a more accurate method for electronic structure calculations.
• To improve the prediction of atomization energies for chemical systems.

Main Methods:

• Predicting the radius of convergence for the density-functional perturbation series.
• Resumming the divergent series using exact exchange and second-order correlation.
• Incorporating explicit density functionals for the strong-interaction limit.

Main Results:

• Successfully predicted the radius of convergence for the perturbation series.
• Developed a new correlation functional.
• Achieved competitive accuracy in predicting atomization energies without typical error cancellation.

Conclusions:

• The developed method offers a viable approach to overcome the divergence of the density-functional perturbation series.
• The new correlation functional, combined with exact exchange, provides accurate atomization energies.
• This work enhances the reliability of electronic structure calculations for various systems.