On the use of property-oriented basis sets for the simulation of vibrational chiroptical spectroscopies

Abstract

We computed vibrational circular dichroism (VCD) and Raman optical activity (ROA) spectra for a test set of six chiral compounds using two standard density-functionals and an array of basis sets. We analysed the performance of property-oriented basis sets using a quadruple-zeta basis as a reference against four key metrics. We find little qualitative difference between the spectra produced by the larger basis sets (ORP, LPolX, aug-cc-pVTZ, and aug-cc-pVQZ), though their quantitative metrics exhibit wide variations. The smaller basis sets (rDPS, augD-3-21G, augT3-3-21G, Sadlej-pVTZ, and aug-cc-pVDZ) performed better for VCD rotatory strengths than for the corresponding ROA circular intensity differences (CIDs). However, this trend diminishes as the basis-set size is increased, lending validity to the conclusion that more robust property-oriented basis sets are required for ROA spectral generation than that of VCD. We observed improved performance in the mid-infrared region compared to the high-frequency regime, as well as overestimation of VCD rotatory strengths in the latter region as compared to the reference. We conclude that the ORP and LPol-ds basis sets are the most efficient and effective choices of basis set for the prediction of VCD and ROA spectra, as they provide both highly accurate results at reduced computational expense.

GRAPHICAL ABSTRACT

Keywords:

• Density-functional theory
• chirality
• vibrational circular dichroism
• Raman optical activity

Acknowledgments

The authors are grateful to Advanced Research Computing at Virginia Tech for providing computational resources and technical support that have contributed to the results reported within the paper. The authors would like to dedicate this work to the memory of Dr. Timothy J. Lee, a collaborator, mentor, and dear friend of TDC.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was supported by the U.S. National Science Foundation (grant DMR- 1933525), and EHF was supported by an undergraduate research fellowship (grant DMR-2244483).