2024/06/22 by Joseph P. Heindel, Heindel, Joseph P., Selim Sami +3 · 2 citations
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Computer science #Environmental science #Physics #Spectroscopy and Quantum Chemical Studies #Statistical physics
paper · pdf · doi:10.48550/arxiv.2406.15944
published in arXiv (Cornell University) (Cornell University)
openalex publication_date 2024/06/22 · openalex created_date 2024/06/26 · openalex updated_date 2026/08/06
We introduce a general framework for many-body force field models, the Completely Multipolar Model (CMM), that utilizes multipolar electrical moments modulated by exponential decay of electron density as a common functional form for all piecewise terms of an energy decomposition analysis of intermolecular interactions. With this common functional form the CMM model establishes well-formulated damped tensors that reach the correct asymptotes at both long- and short-range while formally ensuring no short-range catastrophes. The CMM describes the separable EDA terms of dispersion, exchange polarization, and Pauli repulsion with short-ranged anisotropy, polarization as intramolecular charge fluctuations and induced dipoles, while charge transfer describes explicit movement of charge between molecules, and naturally describes many-body charge transfer by coupling into the polarization equations. We also utilize a new one-body potential that accounts for intramolecular polarization by including an electric field-dependent correction to the Morse potential to ensure that the CMM reproduces all physically relevant monomer properties including the dipole moment, molecular polarizability, and dipole and polarizability derivatives. The quality of the CMM is illustrated through agreement of individual terms of the EDA and excellent extrapolation to energies and geometries of an extensive validation set of water cluster data.