Optimal finite-range atomic basis sets for liquid water and ice

Area of Science:

• Computational Chemistry
• Materials Science
• Quantum Mechanics

Background:

• Finite-range numerical atomic orbitals are crucial for first-principles calculations.
• Generating and validating these basis sets presents a significant challenge for users.

Purpose of the Study:

• To present a novel scheme for generating improved finite-range polarization orbitals.
• To develop and evaluate high-accuracy atomic orbital basis sets for the water molecule.

Main Methods:

• Development of a new scheme for generating polarization orbitals.
• Creation of a series of high-accuracy basis sets for water.
• Performance testing via comparison with plane-wave calculations.

Main Results:

• The new atomic orbital basis sets demonstrate excellent transferability and consistency.
• Highest-order basis sets (quadruple-ζ) achieve accuracy comparable to ~1000 eV plane-wave cutoffs for energies and forces.
• Significantly improved accuracy for total energies and absolute pressures was observed.

Conclusions:

• The developed basis sets offer a robust and accurate alternative to plane-wave methods for condensed water phases.
• This work addresses the challenge of basis set generation, enhancing usability for computational chemists.