Effective fully polarizable QM/MM approaches to compute Raman and Raman Optical Activity spectra in aqueous solution

Chiara Sepali; Piero Lafiosca; Sara Gómez; Tommaso Giovannini; Chiara Cappelli

doi:10.1016/j.saa.2023.123485

Effective fully polarizable QM/MM approaches to compute Raman and Raman Optical Activity spectra in aqueous solution

Spectrochim Acta A Mol Biomol Spectrosc. 2024 Jan 15:305:123485. doi: 10.1016/j.saa.2023.123485. Epub 2023 Oct 5.

Authors

Chiara Sepali¹, Piero Lafiosca¹, Sara Gómez¹, Tommaso Giovannini¹, Chiara Cappelli²

Affiliations

¹ Scuola Normale Superiore, Piazza dei Cavalieri, 7, Pisa, 56126, Italy.
² Scuola Normale Superiore, Piazza dei Cavalieri, 7, Pisa, 56126, Italy. Electronic address: chiara.cappelli@sns.it.

PMID: 37827000
DOI: 10.1016/j.saa.2023.123485

Abstract

Raman and Raman Optical Activity (ROA) signals are amply affected by solvent effects, especially in the presence of strongly solute-solvent interactions such as Hydrogen Bonding (HB). In this work, we extend the fully atomistic polarizable Quantum Mechanics/Molecular Mechanics approach, based on the Fluctuating Charges and Fluctuating Dipoles force field to the calculation of Raman and ROA spectra. Such an approach is able to accurately describe specific HB interactions, by also accounting for anisotropic contributions due to the inclusion of fluctuating dipoles. To highlight the potentiality of the novel approach, Raman and ROA spectra of L-Serine and L-Cysteine dissolved in aqueous solution are computed and compared both with alternative theoretical approaches and experimental measurements.

Keywords: Hydrogen bonding; Molecular dynamics; QM/MM; ROA; Raman; Solvent effects.