Exact on-event expressions for discrete potential systems

Marcus N. Bannerman, Leo Lue

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The properties of systems composed of atoms interacting though discrete potentials are dictated by a series of events which occur between pairs of atoms. There are only four basic event types for pairwise discrete potentials and the square-well/shoulder systems studied here exhibit them all. Closed analytical expressions are derived for the on-event kinetic energy distribution functions for an atom, which are distinct from the Maxwell-Boltzmann distribution function. Exact expressions are derived that directly relate the pressure and temperature of equilibrium discrete potential systems to the rates of each type of event. The pressure can be determined from knowledge of only the rate of core and bounce events. The temperature is given by the ratio of the number of bounce events to the number of disassociation/association events. All these expressions are validated with event-driven molecular dynamics simulations and agree with the data within the statistical precision of the simulations.
LanguageEnglish
Article number124506
Number of pages12
JournalJournal of Chemical Physics
Volume133
Issue number12
DOIs
Publication statusPublished - 24 Sep 2010

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Atoms
Distribution functions
Kinetic energy
Molecular dynamics
Association reactions
Temperature
distribution functions
Computer simulation
atoms
Boltzmann distribution
square wells
shoulders
energy distribution
simulation
kinetic energy
molecular dynamics
temperature

Keywords

  • association
  • atom-atom collisions
  • dissociation
  • molecular dynamics method
  • potential energy functions
  • statistical mechanics

Cite this

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Exact on-event expressions for discrete potential systems. / Bannerman, Marcus N.; Lue, Leo.

In: Journal of Chemical Physics, Vol. 133, No. 12, 124506, 24.09.2010.

Research output: Contribution to journalArticle

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