### 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. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3486567]

Original language | English |
---|---|

Number of pages | 12 |

Journal | The Journal of Chemical Physics |

Volume | 133 |

Issue number | 12 |

DOIs | |

Publication status | Published - 28 Sep 2010 |

### Keywords

- square-well fluid
- molecular dynamical calculations
- Monte-Carlo simulations
- equation-of-state
- transport-properties
- shoulder fluids
- thermal-conductivity
- computer-simulations
- critical-behavior
- phase-equilibria

### Cite this

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

Research output: Contribution to journal › Article

*The Journal of Chemical Physics*, vol. 133, no. 12. https://doi.org/10.1063/1.3486567

}

TY - JOUR

T1 - Exact on-event expressions for discrete potential systems

AU - Bannerman, Marcus N.

AU - Lue, Leo

PY - 2010/9/28

Y1 - 2010/9/28

N2 - 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. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3486567]

AB - 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. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3486567]

KW - square-well fluid

KW - molecular dynamical calculations

KW - Monte-Carlo simulations

KW - equation-of-state

KW - transport-properties

KW - shoulder fluids

KW - thermal-conductivity

KW - computer-simulations

KW - critical-behavior

KW - phase-equilibria

U2 - 10.1063/1.3486567

DO - 10.1063/1.3486567

M3 - Article

VL - 133

JO - The Journal of Chemical Physics

JF - The Journal of Chemical Physics

SN - 0021-9606

IS - 12

ER -