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Absorption Properties of Large Complex Molecular Systems: The DFTB/Fluctuating Charge Approach.

ABSTRACT: We report on the first formulation of a novel polarizable QM/MM approach, where the density functional tight binding (DFTB) is coupled to the fluctuating charge (FQ) force field. The resulting method (DFTB/FQ) is then extended to the linear response within the TD-DFTB framework and challenged to study absorption spectra of large condensed-phase systems.

SUBMITTER: Lafiosca P

PROVIDER: S-EPMC8908768 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Absorption Properties of Large Complex Molecular Systems: The DFTB/Fluctuating Charge Approach.

Lafiosca Piero P Gómez Sara S Giovannini Tommaso T Cappelli Chiara C

Journal of chemical theory and computation 20220220 3

We report on the first formulation of a novel polarizable QM/MM approach, where the density functional tight binding (DFTB) is coupled to the fluctuating charge (FQ) force field. The resulting method (DFTB/FQ) is then extended to the linear response within the TD-DFTB framework and challenged to study absorption spectra of large condensed-phase systems. ...[more]

PMID: 35184553

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