The Compadre Portal website will be unavailable Friday evening through Saturday afternoon as electrical work occurs in the American Center of Physics server room. Down time will begin at 6PM Eastern Time on Friday. Service is expected to resume by 6PM on Saturday, July 30.

Lennard-Jones Potential Model Documents

This material has 2 associated documents. Select a document title to view a document's information.

Main Document

Lennard-Jones Potential Model 

written by Wolfgang Christian

The EJS Lennard-Jones Potential model shows the dynamics of a particle of mass m within this potential.  You can drag particle to change its position and you can drag the energy-line to change its total energy.

The Lennard-Jones potential function is a reasonably accurate model of interactions between noble gas atoms.  The binding energy epsilon is the depth of the potential well and minimum molecular separation are set equal to unity.  This simulation uses uses a natural system of units the mass and the depth of the Lennard-Jones potential set equal to 1. For argon (for example), the unit of distance is 3.4 angstroms, the unit of mass is 40 atomic mass units, and the unit of energy is 0.01 electron-volts; the corresponding unit of time is then 2.2 picoseconds, the unit of velocity is 160 meters per second.

The Lennard-Jones Potential model was created using the Easy Java Simulations (Ejs) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_stp_md_LennardJones.jar.jar file will run the program if Java is installed.  Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models.  Additional Ejs models for classical mechanics are available.  They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Last Modified June 10, 2014

This file has previous versions.

Source Code Documents

Lennard-Jones Potential Source Code 

The source code zip archive contains an XML representation of the Lennard-Jones Potential Model.  Unzip this archive in your Ejs workspace to compile and run this model using Ejs.

Last Modified June 10, 2014

This file has previous versions.