Segmented contracted basis sets optimized for nuclear magnetic shielding.

Area of Science:

• Computational chemistry
• Quantum chemistry
• Spectroscopy

Background:

• Nuclear magnetic shielding constants are crucial for interpreting NMR spectra.
• Existing basis sets may not offer optimal efficiency or accuracy for these calculations.
• Developing specialized basis sets can improve computational performance.

Purpose of the Study:

• To introduce and evaluate a new family of segmented contracted basis sets (pcSseg-n) for calculating nuclear magnetic shielding constants.
• To assess the computational efficiency and accuracy of these sets compared to existing methods.
• To extend the applicability of these basis sets to a broader range of elements.

Main Methods:

• Optimization of segmented contracted basis sets (pcSseg-n) at the density functional theory (DFT) level.
• Testing the basis sets for calculating nuclear magnetic shielding constants for elements H-Kr.
• Comparison with previously developed general contracted basis sets (pcS-n).

Main Results:

• The proposed pcSseg-n basis sets demonstrate improved computational efficiency for elements H-Ar compared to pcS-n sets.
• The basis sets are extended to include elements K-Kr.
• pcSseg-n sets are effective for both DFT and correlated wave function methods.
• Basis sets are available in various qualities (double-ζ to pentuple-ζ).

Conclusions:

• The pcSseg-n basis sets provide an efficient and accurate tool for calculating nuclear magnetic shielding constants.
• These sets are versatile, suitable for routine and benchmark calculations across many elements.
• The ability to separate basis set and method errors will facilitate the development of more accurate computational methods.