Polarized Gaussian basis sets from one-electron ions.

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Electronic Structure Theory

Background:

• Accurate electronic structure calculations are crucial for understanding molecular properties.
• Traditional methods for generating basis sets can be computationally intensive and complex.
• Existing universal Gaussian basis sets (UGBS) may exhibit significant errors for certain elements.

Purpose of the Study:

• To develop a novel, simplified approach for generating accurate basis sets for electronic structure calculations.
• To demonstrate the efficacy of basis sets derived from one-electron hydrogenic ions.
• To extend this methodology for creating polarized basis sets applicable to all elements.

Main Methods:

• Derivation of basis sets from accuracy considerations for hydrogenic one-electron ions (Y^(Y-1)+).
• Utilizing even-tempered basis sets with parameters optimized from the Z^(Z-1)+ configuration.
• Energy optimization of even-tempered parameters for all elements (1 ≤ Z ≤ 118).
• Generation of polarization shells using the same first-principles approach.

Main Results:

• Even-tempered basis sets with UGBS parameters outperform UGBS, yielding higher accuracy for Hartree-Fock total energies.
• The new method successfully generates accurate, energy-optimized basis sets for all elements in the Periodic Table.
• Calculations on molecules demonstrate that the polarized basis sets achieve chemical accuracy, even for challenging systems like SF₆.

Conclusions:

• A straightforward, first-principles approach enables the generation of accurate and efficient basis sets for electronic structure calculations.
• This method eliminates the need for self-consistent field calculations in basis set generation.
• The approach is readily extendable to relativistic calculations and can aid in exploring elements beyond the current Periodic Table.