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Lennard-Jones 2D Demon Model Documents

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Main Document

Lennard-Jones 2D Demon Model 

written by Wolfgang Christian

The Lennard-Jones 2D Demon Model is a Monte Carlo simulation of  Lennard-Jones particles in two dimensions interacting with a Monte Carlo demon.  A Monte Carlo demon is an extra degree of freedom that is allowed to transfer energy as it attempts to change the state of the system. The demon keeps track of its own energy and can take or give energy to a particle as it interacts with a randomly chosen particle. Because the demon cannot have negative energy, the total energy of the system remains constant -- as it should in the microcanonical ensemble. The demon is, in effect, a thermometer. Its extra degree of freedom perturbs the system very little and the average demon energy is proportional to the temperature of the system. (See Statistical and Thermal Physics notes by H. Gould and J. Tobochnik.)

The Lennard-Jones 2D Demon Model was developed using the Easy Java/JavaScript Simulations (EjsS) version 5 modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.

Published August 1, 2014
Last Modified August 1, 2014

This file has previous versions.

Source Code Documents

Lennard-Jones 2D Demon Source Code 

The source code zip archive contains an XML representation of the Lennard-Jones 2D Demon Model.   Unzip this archive in your EjsS workspace to compile and run this model using EjsS ver 5.

Last Modified August 1, 2014

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