Saved in:
Bibliographic Details
Main Authors: Fay, Thomas P., Ferré, Nicolas, Huix-Rotllant, Miquel
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2409.10483
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917866721247232
author Fay, Thomas P.
Ferré, Nicolas
Huix-Rotllant, Miquel
author_facet Fay, Thomas P.
Ferré, Nicolas
Huix-Rotllant, Miquel
contents Electronic polarization and dispersion are decisive actors in determining interaction energies between molecules. These interactions have a particularly profound effect on excitation energies of molecules in complex environments, especially when the excitation involves a significant degree of charge reorganisation. The direct reaction field (DRF) approach, which has seen a recent revival of interest, provides a powerful framework for describing these interactions in quantum mechanics/molecular mechanics (QM/MM) models of systems, where a small subsystem of interest is described using quantum chemical methods and the remainder is treated with a simple MM force field. In this paper we show how the DRF approach can be combined with the electrostatic potential fitted (ESPF) multipole operator description of the QM region charge density, which significantly improves the efficiency of the method, particularly for large MM systems, and for typical calculations effectively eliminates the dependence on MM system size. We also show how the DRF approach can be combined with fluctuating charge descriptions of the polarizable environment, as well as previously used atom-centred dipole-polarizability based models. We further show that the ESPF-DRF method provides an accurate description of molecular interactions in both ground and excited electronic states of the QM system and apply it to predict the gas to aqueous solution solvatochromic shifts in the UV/visible absorption spectrum of acrolein.
format Preprint
id arxiv_https___arxiv_org_abs_2409_10483
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Efficient polarizable QM/MM using the direct reaction field Hamiltonian with electrostatic potential fitted multipole operators
Fay, Thomas P.
Ferré, Nicolas
Huix-Rotllant, Miquel
Chemical Physics
Electronic polarization and dispersion are decisive actors in determining interaction energies between molecules. These interactions have a particularly profound effect on excitation energies of molecules in complex environments, especially when the excitation involves a significant degree of charge reorganisation. The direct reaction field (DRF) approach, which has seen a recent revival of interest, provides a powerful framework for describing these interactions in quantum mechanics/molecular mechanics (QM/MM) models of systems, where a small subsystem of interest is described using quantum chemical methods and the remainder is treated with a simple MM force field. In this paper we show how the DRF approach can be combined with the electrostatic potential fitted (ESPF) multipole operator description of the QM region charge density, which significantly improves the efficiency of the method, particularly for large MM systems, and for typical calculations effectively eliminates the dependence on MM system size. We also show how the DRF approach can be combined with fluctuating charge descriptions of the polarizable environment, as well as previously used atom-centred dipole-polarizability based models. We further show that the ESPF-DRF method provides an accurate description of molecular interactions in both ground and excited electronic states of the QM system and apply it to predict the gas to aqueous solution solvatochromic shifts in the UV/visible absorption spectrum of acrolein.
title Efficient polarizable QM/MM using the direct reaction field Hamiltonian with electrostatic potential fitted multipole operators
topic Chemical Physics
url https://arxiv.org/abs/2409.10483