Accelerating Analytic-Continuation GW Calculations with a Laplace Transform and Natural Auxiliary Functions

Area of Science:

• Quantum Chemistry
• Computational Physics

Background:

• Accurate prediction of molecular properties is crucial in quantum chemistry.
• Existing methods for Green\'s function (GW) calculations can be computationally intensive.

Purpose of the Study:

• To develop a more efficient and accurate Green\'s function (GW) implementation.
• To reduce the computational cost of post-self-consistent field calculations.

Main Methods:

• Combined Laplace transform (LT) with natural auxiliary functions and frozen-core approximation for GW calculations.
• Integrated the LT-GW approach into existing quantum chemistry frameworks.
• Applied the Bethe-Salpeter equation with an efficient implementation.

Main Results:

• Demonstrated a small prefactor for computational scaling.
• Showcased easy integration into current molecular GW codes.
• Achieved significant performance improvements for large systems (up to 352 atoms).

Conclusions:

• The LT-GW approach offers a computationally efficient and accurate method for quantum chemistry.
• This method is readily applicable to various systems and can be easily integrated.
• The combination with Bethe-Salpeter equation further enhances its utility.