Interpolative Separable Density Fitting Decomposition for Accelerating Hybrid Density Functional Calculations with...

Area of Science:

• Computational Materials Science
• Quantum Chemistry
• Electronic Structure Theory

Background:

• Hybrid density functional theory (DFT) methods are crucial for accurate electronic structure calculations but are computationally expensive.
• Existing methods face challenges in efficiently handling the exchange operator, limiting the scale of simulations.
• The development of novel computational techniques is essential to overcome these limitations.

Purpose of the Study:

• To present a new, efficient computational method for hybrid DFT-based electronic structure calculations.
• To significantly reduce the computational cost associated with the exchange operator in DFT.
• To enable accurate and fast calculations for large-scale material systems.

Main Methods:

• Introduced an interpolative separable density fitting (ISDF) procedure to approximate matrices of orbital products.
• Combined ISDF with the adaptively compressed exchange (ACE) operator formalism.
• Reduced the number of Poisson solves and exchange operator updates, decreasing computational complexity.

Main Results:

• The ACE-ISDF method reduces computational cost by nearly two orders of magnitude for large systems.
• Achieved converged hybrid functional calculations for a 1000-atom silicon system in under 10 minutes.
• Demonstrated accurate energies and forces for both insulating and metallic systems, with excellent scalability.

Conclusions:

• The ACE-ISDF method offers a significant advancement in the efficiency of hybrid DFT calculations.
• This method enables accurate electronic structure computations for large, complex material systems.
• ACE-ISDF provides results closer to experimental values compared to traditional semilocal functionals.