Black-box inhomogeneous preconditioning for self-consistent field iterations in density functional theory.

Area of Science:

• Computational physics
• Materials science
• Quantum chemistry

Background:

• Kohn-Sham density functional theory (KS-DFT) is crucial for electronic structure calculations.
• Convergence issues, like long-range charge sloshing, hinder KS-DFT in large, inhomogeneous systems (e.g., clusters, surfaces).
• Existing methods may be computationally expensive or less effective for diverse material types.

Purpose of the Study:

• To introduce a novel, efficient preconditioner for accelerating self-consistent KS-DFT calculations.
• To address and resolve convergence challenges, specifically long-range charge sloshing.
• To provide a versatile preconditioner applicable across various material classes, including metals, insulators, and semiconductors.

Main Methods:

• Development of a preconditioner based on the local density of states.
• Utilizing a parameter-free, physically motivated approximation of the independent-particle susceptibility operator.
• Extension to semiconductors via the macroscopic electronic dielectric constant.

Main Results:

• The proposed preconditioner effectively cures long-range charge sloshing.
• Demonstrated successful application on inhomogeneous systems comprising metals, insulators, semiconductors, and vacuum.
• The method is computationally inexpensive.

Conclusions:

• The new local density of states-based preconditioner offers a significant advancement for KS-DFT.
• It provides a robust and efficient solution for achieving convergence in complex material simulations.
• The preconditioner's versatility makes it valuable for a wide range of computational materials science applications.