Electrostatically Embedded Many-Body Expansion for Large Systems, with Applications to Water Clusters

A new machine learning based approach combining support vector regression (SVR) and many body expansion (MBE) that can predict the interaction energies of water clusters with high accuracy (for decamers: 2.78% of QM estimates).

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Nature of Many-Body Forces in Water Clusters and Bulk

Water in Confining Geometries - Springer Series in Cluster Physics ◽

10.1007/978-3-662-05231-0_2 ◽

2003 ◽

pp. 7-23 ◽

Cited By ~ 2

Author(s):

Krzysztof Szalewicz ◽

Robert Bukowski ◽

Bogumil Jeziorski

Keyword(s):

Water Clusters ◽

Many Body ◽

Body Forces

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Understanding the many-body expansion for large systems. III. Critical role of four-body terms, counterpoise corrections, and cutoffs

The Journal of Chemical Physics ◽

10.1063/1.4986110 ◽

2017 ◽

Vol 147 (16) ◽

pp. 161729 ◽

Cited By ~ 11

Author(s):

Kuan-Yu Liu ◽

John M. Herbert

Keyword(s):

Critical Role ◽

Many Body ◽

Counterpoise Corrections ◽

Large Systems ◽

The Many

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Many‐body effects in tetrahedral water clusters

The Journal of Chemical Physics ◽

10.1063/1.455059 ◽

1988 ◽

Vol 89 (4) ◽

pp. 2149-2159 ◽

Cited By ~ 48

Author(s):

Kersti Hermansson

Keyword(s):

Water Clusters ◽

Many Body ◽

Many Body Effects

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Data-Driven Many-Body Models Enable a Quantitative Description of Chloride Hydration from Clusters to Bulk

10.26434/chemrxiv.14755449 ◽

2021 ◽

Author(s):

Alessandro Caruso ◽

Francesco Paesani

Keyword(s):

Water Clusters ◽

Quantitative Description ◽

Predictive Ability ◽

Chloride Ion ◽

Potential Energy Function ◽

Data Driven ◽

Quantum Molecular Dynamics ◽

Many Body ◽

Chloride Water ◽

Body Energy

<div> <div> <div> <p>We present a new data-driven potential energy function (PEF) describing chloride–water interactions which is developed within the many-body-energy (MB-nrg) theoretical framework. Besides quantitatively reproducing low-order many-body energy contributions, the new MB-nrg PEF is able to correctly predict the interaction energies of small chloride–water clusters calculated at the coupled cluster level of theory. Importantly, classical and quantum molecular dynamics simulations of a single chloride ion in water demonstrate that the new MB-nrg PEF predicts X-ray spectra in close agreement with the experimental results. Comparisons with an popular empirical model and a polarizable PEF emphasize the importance of an accurate representation of short-range many-body effect while demonstrating that pairwise additive representations of chloride–water and water–water interactions are inadequate for correctly representing the hydration structure of chloride in both gas-phase clusters and solution. We believe that the analyses presented in this study provide additional evidence for the accuracy and predictive ability of the MB-nrg PEFs which can then enable more realistic simulations of ionic aqueous systems in different environments. </p> </div> </div> </div>

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Data-Driven Many-Body Models Enable a Quantitative Description of Chloride Hydration from Clusters to Bulk

10.26434/chemrxiv.14755449.v1 ◽

2021 ◽

Author(s):

Alessandro Caruso ◽

Francesco Paesani

Keyword(s):

Water Clusters ◽

Quantitative Description ◽

Predictive Ability ◽

Chloride Ion ◽

Potential Energy Function ◽

Data Driven ◽

Quantum Molecular Dynamics ◽

Many Body ◽

Chloride Water ◽

Body Energy

<div> <div> <div> <p>We present a new data-driven potential energy function (PEF) describing chloride–water interactions which is developed within the many-body-energy (MB-nrg) theoretical framework. Besides quantitatively reproducing low-order many-body energy contributions, the new MB-nrg PEF is able to correctly predict the interaction energies of small chloride–water clusters calculated at the coupled cluster level of theory. Importantly, classical and quantum molecular dynamics simulations of a single chloride ion in water demonstrate that the new MB-nrg PEF predicts X-ray spectra in close agreement with the experimental results. Comparisons with an popular empirical model and a polarizable PEF emphasize the importance of an accurate representation of short-range many-body effect while demonstrating that pairwise additive representations of chloride–water and water–water interactions are inadequate for correctly representing the hydration structure of chloride in both gas-phase clusters and solution. We believe that the analyses presented in this study provide additional evidence for the accuracy and predictive ability of the MB-nrg PEFs which can then enable more realistic simulations of ionic aqueous systems in different environments. </p> </div> </div> </div>

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Infrared Signatures of Isomer Selectivity and Symmetry Breaking in the Cs+(H2O)3 Complex Using Many-Body Potential Energy Functions

10.26434/chemrxiv.12275372.v1 ◽

2020 ◽

Author(s):

Marc Riera ◽

Justin J. Talbot ◽

Ryan P. Steele ◽

Francesco Paesani

Keyword(s):

Potential Energy ◽

Potential Energy Surface ◽

Energy Surface ◽

Water Clusters ◽

Quantitative Description ◽

Experimental Spectrum ◽

Many Body ◽

Energy Functions ◽

Potential Energy Functions ◽

Three Body

<div> <div> <div> <p>A quantitative description of the interactions between ions and water is key to characterizing the role played by ions in mediating fundamental processes that take place in aqueous environments. At the molecular level, vibrational spectroscopy provides a unique means to probe the multidimensional potential energy surface of small ion−water clusters. In this study, we combine the MB-nrg potential energy functions recently developed for ion−water interactions with perturbative corrections to vibrational self-consistent field theory and the local-monomer approximation to disentangle many-body effects on the stability and vibrational structure of the Cs+(H2O)3 cluster. Since several low-energy, thermodynamically accessible isomers exist for Cs+(H2O)3, even small changes in the description of the underlying potential energy surface can result in large differences in the relative stability of the various isomers. Our analysis demonstrates that a quantitative account for three-body energies and explicit treatment of cross-monomer vibrational couplings are required to reproduce the experimental spectrum. </p> </div> </div> </div>

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Elevating Density Functional Theory to Chemical Accuracy for Water Simulations through a Density-Corrected Many-Body Formalism

10.33774/chemrxiv-2021-hstgf-v3 ◽

2021 ◽

Author(s):

Saswata Dasgupta ◽

Eleftherios Lambros ◽

John Perdew ◽

Francesco Paesani

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Water Clusters ◽

Potential Energy Function ◽

Data Driven ◽

Coupled Cluster ◽

Many Body ◽

Functional Theory ◽

Dynamics Simulations ◽

Body Potential

Density functional theory (DFT) has been extensively used to model the properties of water. Albeit maintaining a good balance between accuracy and efficiency, no density functional has so far achieved the degree of accuracy necessary to correctly predict the properties of water across the entire phase diagram. Here, we present density-corrected SCAN (DC-SCAN) calculations for water which, minimizing density-driven errors, elevate the accuracy of the SCAN functional to that of “gold standard” coupled-cluster theory. Building upon the accuracy of DC-SCAN within a many-body formalism, we introduce a data-driven many-body potential energy function, MB-SCAN(DC), that quantitatively reproduces coupled cluster reference values for interaction, binding, and individual many-body energies of water clusters. Importantly, molecular dynamics simulations carried out with MB-SCAN(DC) also reproduce the properties of liquid water, which thus demonstrates that MB-SCAN(DC) is effectively the first DFT-based model that correctly describes water from the gas to the liquid phase.

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Halide Ion Micro-Hydration: Structure, Energetics, and Spectroscopy of Small Halide–Water Clusters

10.26434/chemrxiv.7636004.v1 ◽

2019 ◽

Author(s):

Pushp Bajaj ◽

Marc Riera ◽

Jason K. Lin ◽

Yaira E. Mendoza Montijo ◽

Jessica Gazca ◽

...

Keyword(s):

Water Clusters ◽

Quantitative Description ◽

Three Dimensional ◽

Many Body ◽

Ion Hydration ◽

Potential Energy Functions ◽

Hydrogen Bond Networks ◽

Correct Representation ◽

Dynamics Simulations ◽

Body Potential

<div> <div> <div> <p>Replica exchange molecular dynamics simulations and vibrational spectroscopy calculations are performed using halide-water many-body potential energy functions to provide a bottom-up analysis of the structures, energetics, and hydrogen-bonding arrangements in X−(H2O)n=3−6 clusters, with X = F, Cl, Br, and I. Independently of the cluster size, it is found that all four halides prefer surface-type structures in which they occupy one of the vertices in the underlying three-dimensional hydrogen-bond networks. For fluoride-water clusters, this is in contrast with previous reports suggesting that fluoride prefers interior-type arrangements, where the ion is fully hydrated. These differences can be ascribed to the variability in how various molecular models are capable to reproduce the subtle interplay between halide-water and water-water interactions. Our results thus emphasize the importance of a correct representation of individual many-body contributions to the molecular interactions for a quantitative description of halide ion hydration. </p> </div> </div> </div>

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