A novel Gaussian-Sinc mixed basis set for electronic structure calculations

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Electronic Structure Theory

Background:

• Accurate electronic structure calculations are crucial for understanding chemical properties.
• Existing methods face challenges in efficiently representing both localized and delocalized electronic regions.

Purpose of the Study:

• To introduce and validate a novel Gaussian-Sinc mixed basis set methodology.
• To demonstrate its effectiveness for Hartree-Fock electronic structure calculations.

Main Methods:

• Developed a mixed basis set combining atom-centered Gaussian functions and orthonormal sinc functions on a lattice.
• Implemented a dimensional separated methodology for computing Coulomb integrals.
• Ensured translational invariance and satisfied boundary conditions.

Main Results:

• Calculated ground-state Hartree-Fock energies for atoms (up to Neon), diatomic molecules (H2, O2, N2), and benzene.
• Demonstrated the ability to represent all-electron electronic structure across localized and delocalized regions.

Conclusions:

• The Gaussian-Sinc mixed basis set offers a flexible and accurate approach for electronic structure calculations.
• This method shows significant advantages over previous computational techniques.