Projected Commutator DIIS Method for Accelerating Hybrid Functional Electronic Structure Calculations.

Area of Science:

• Quantum Chemistry
• Computational Physics
• Materials Science

Background:

• The Commutator Direct Inversion in Iterative Subspace (C-DIIS) method accelerates self-consistent field (SCF) iterations in quantum chemistry.
• C-DIIS requires significant memory for large basis sets, limiting its application.

Purpose of the Study:

• To develop a novel method enabling C-DIIS for large basis sets like plane waves.
• To enhance the efficiency of electronic structure calculations and molecular dynamics simulations.

Main Methods:

• Developed the Projected Commutator Direct Inversion in Iterative Subspace (PC-DIIS) method.
• Utilized projection onto a gauge-fixing matrix to reduce computational cost.
• Applied PC-DIIS to Kohn-Sham density functional theory with hybrid functionals and ab initio molecular dynamics.

Main Results:

• PC-DIIS efficiently handles large basis sets, comparable in cost to standard charge mixing schemes.
• The method is gauge-invariant, ensuring stable performance.
• PC-DIIS significantly reduces SCF iterations compared to existing methods for hybrid functionals.
• Extrapolation of the gauge-fixing matrix accelerates molecular dynamics simulations.

Conclusions:

• PC-DIIS extends C-DIIS applicability to large basis sets, overcoming previous limitations.
• The new method offers superior performance for accelerating SCF iterations in demanding quantum chemistry calculations.
• PC-DIIS provides an efficient strategy for ab initio molecular dynamics simulations with hybrid functionals.