RMDff: A smoothly transitioning, forcefield-based representation of kinetics for reactive molecular dynamics simulations

Abstract

RMDff is a new forcefield that smoothly couples the reactive intersections of potential energy surfaces to model chemical reactions. The method uses switching functions to accomplish a smooth transition from reactant to product atom types. This paper demonstrates and tests RMDff for homolytic scissions. The reaction networks are described by localized events involving only a few atoms, so that the complex mechanisms employed in conventional kinetics modeling are not needed. Unlike quantum chemical calculations, which are feasible only for small molecules, this new valence-bond forcefield can be coupled with Reactive Molecular Dynamics to describe chemical reactions in large domains.

Keywords:

• Molecular dynamics
• Forcefields
• Reactive forcefield
• Kinetics
• Homolysis

Acknowledgements

K. D. Smith and P. R. Westmoreland were supported through Cluster F of the Center for UMass-Industry Research on Polymers, a consortium sponsored by US Army, Boeing, DuPont, FAA, General Electric, Schneller, Solvay, NIST, Rogers, Johns Manville, Multina and International Association of Fire Fighters. The facility for some of the ab initio calculations were supported by the National Science Foundation under the following NSF programs: Partnerships for Advanced Computational Infrastructure, Distributed Terascale Facility (DTF) and Terascale Extensions: Enhancements to the Extensible Terascale Facility, whose support is appreciated.

Notes

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Additional information

Notes on contributors

K. D. Smith

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S. I. Stoliarov

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M. R. Nyden

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