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Simulating Absorption Spectra of Flavonoids in Aqueous Solution: A Polarizable QM/MM Study.

ABSTRACT: We present a detailed computational study of the UV/Vis spectra of four relevant flavonoids in aqueous solution, namely luteolin, kaempferol, quercetin, and myricetin. The absorption spectra are simulated by exploiting a fully polarizable quantum mechanical (QM)/molecular mechanics (MM) model, based on the fluctuating charge (FQ) force field. Such a model is coupled with configurational sampling obtained by performing classical molecular dynamics (MD) simulations. The calculated QM/FQ spectra are compared with the experiments. We show that an accurate reproduction of the UV/Vis spectra of the selected flavonoids can be obtained by appropriately taking into account the role of configurational sampling, polarization, and hydrogen bonding interactions.

SUBMITTER: Skoko S

PROVIDER: S-EPMC7764712 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Simulating Absorption Spectra of Flavonoids in Aqueous Solution: A Polarizable QM/MM Study.

Skoko Sulejman S Ambrosetti Matteo M Giovannini Tommaso T Cappelli Chiara C

Molecules (Basel, Switzerland) 20201211 24

We present a detailed computational study of the UV/Vis spectra of four relevant flavonoids in aqueous solution, namely luteolin, kaempferol, quercetin, and myricetin. The absorption spectra are simulated by exploiting a fully polarizable quantum mechanical (QM)/molecular mechanics (MM) model, based on the fluctuating charge (FQ) force field. Such a model is coupled with configurational sampling obtained by performing classical molecular dynamics (MD) simulations. The calculated QM/FQ spectra ar ...[more]

PMID: 33322361

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