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Published on: February 18, 2014
Microscopic expressions for the thermodynamic temperature
1Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia.
Summary
Arbitrary phase space vector fields can generate phase functions that yield thermodynamic temperature. These functions are validated for periodic boundary systems and molecular dynamics simulations.
Area of Science:
- Statistical Mechanics
- Computational Physics
Background:
- Thermodynamic temperature is a fundamental property in statistical mechanics.
- Calculating temperature from molecular dynamics simulations requires robust methods.
Purpose of the Study:
- To introduce a novel method for deriving thermodynamic temperature from phase space vector fields.
- To establish the validity conditions for this new temperature definition.
Main Methods:
- Utilizing arbitrary phase space vector fields to construct phase functions.
- Analyzing ensemble averages of these phase functions.
- Testing the method within the molecular dynamics (MD) ensemble and periodic boundary conditions.
Main Results:
- Demonstrated that ensemble averages of generated phase functions accurately represent thermodynamic temperature.
- Defined conditions under which these phase functions are valid for periodic systems.
- Successfully validated the approach using a short-ranged potential in an MD simulation.
Conclusions:
- Arbitrary phase space vector fields offer a versatile tool for defining thermodynamic temperature.
- The presented method is valid and applicable to molecular dynamics simulations under specific conditions.
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