Electronic Transitions for a Fully Polarizable QM/MM Approach Based on Fluctuating Charges and Fluctuating Dipoles: Linear and Corrected Linear Response Regimes

Abstract

Fully polarizable QM/MM approach based on fluctuating charges and fluctuating dipoles, named QM/FQFμ (J. Chem. Theory Comput. 2019, 15 2233-2245), is extended to the calculation of vertical excitation energies of solvated molecular systems. Excitation energies are defined within two different solvation regimes, i.e. linear response (LR), where the response of the MM portion is adjusted to the QM transition density, and corrected-Linear Response (cLR) in which the MM response is adjusted to the relaxed QM density, thus being able to account for charge equilibration in the excited state. The model, which is specified in terms of three physical parameters (electronegativity, chemical hardness, and polarizability) is applied to vacuo-to-water solvatochromic shifts of aqueous solutions of para-nitroaniline, pyridine and pyrimidine. The results show a good agreement with their experimental counterparts, thus highlighting the potentialities of this approach.

14 pages, 8 figures

References in corpus (3)

• Canonical sampling through velocity-rescaling
• On the Calculation of IR Spectra with a Fully Polarizable QM/MM Approach Based on Fluctuating Charges and Fluctuating Dipoles
• Fully Polarizable QM/Fluctuating Charge Approach to Two-Photon Absorption of Aqueous Solutions

Cited by in corpus (5)

• eT 1.0: an open source electronic structure program with emphasis on coupled cluster and multilevel methods
• Multilevel Density Functional Theory
• Fully Atomistic Modeling of Realistic Plasmonic Materials: Assessing the Performance of Iterative Solvers
• Assessing the Quality of QM/MM Approaches to Describe Vacuo-to-water Solvatochromic Shifts
• Linear Response Properties of Solvated Systems: A Computational Study