Performance of Property-Optimized Basis Sets for Optical Rotation with Coupled Cluster Theory

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Spectroscopy

Background:

• Accurate prediction of optical rotation is crucial for understanding molecular chirality.
• Coupled cluster (CC) methods are high-accuracy computational tools for electronic structure calculations.
• Basis set choice significantly impacts the accuracy of calculated optical rotation values.

Purpose of the Study:

• To evaluate the effectiveness of a newly developed optical rotation prediction (ORP) basis set.
• To assess ORP basis set performance for specific rotation calculations at the coupled cluster (CC) level.
• To investigate the necessity of specialized basis sets for second-row atoms in optical rotation predictions.

Main Methods:

• Development of the ORP basis set for second-row atoms (S, P, Cl).
• Calculation of optical rotations using coupled cluster singles and doubles (CCSD) and CC2 methods.
• Utilized correlation-consistent aug-cc-pVDZ and aug-cc-pVTZ basis sets, extrapolated to the complete basis-set (CBS) limit.
• Preliminary evaluation using time-dependent density-functional theory (TD-DFT) for seven molecules.

Main Results:

• ORP basis set calculations for molecules with only first-row atoms showed favorable agreement with the larger aug-cc-pVTZ basis set.
• In some cases, ORP results for first-row compounds were closer to the estimated complete basis-set (CBS) limit.
• Calculations involving second-row atoms indicated that larger correlation-consistent basis sets are needed for reliable CBS limit estimations.

Conclusions:

• The ORP basis set is effective for predicting optical rotations of chiral molecules containing first-row atoms.
• Specialized and larger basis sets are required for accurate optical rotation predictions of molecules with second-row atoms.
• Further development may be needed to extend the applicability of ORP basis sets to a wider range of chemical systems.