Extending Density-Corrected Density Functional Theory to Large Molecular Systems.

Area of Science:

• Computational chemistry
• Quantum chemistry
• Materials science

Background:

• Practical density-corrected density functional theory (DC-DFT) calculations often depend on computationally intensive Hartree-Fock (HF) densities, limiting their application to large systems.
• Estimating HF densities for systems exceeding a hundred atoms presents a significant computational bottleneck.

Purpose of the Study:

• To enhance the applicability of Hartree-Fock density-corrected density functional theory (HF-DC-DFT) for large molecular systems.
• To introduce and validate the dual-basis method for accelerating HF density calculations.

Main Methods:

• The dual-basis method was employed, utilizing a smaller basis set's density matrix to approximate the HF solution on a larger basis set.
• The approach was benchmarked on diverse systems, including the GMTKN55 database (main-group chemistry) and L7/S6L datasets (large molecular systems).
• A recent reparameterization of HF-r2SCAN-DC4 was detailed, assessing its performance impact.

Main Results:

• The dual-basis method demonstrated significant efficacy in accelerating HF density estimations for large systems.
• Benchmarks confirmed the method's accuracy and reliability across various chemical systems.
• Applications to DNA and HIV systems showed comparable results to existing literature methods.

Conclusions:

• The dual-basis method effectively extends the practical scope of HF-DC-DFT calculations to larger and more complex molecular systems.
• This computational acceleration opens new avenues for studying intricate biological and chemical structures.
• The HF-r2SCAN-DC4 reparameterization maintains performance, ensuring continued accuracy in DC-DFT applications.