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The free energy of expansion and contraction: treatment of arbitrary systems using the Jarzynski equality
Stuart J Davie1, James C Reid, Debra J Searles
1Queensland Micro- and Nanotechnology Centre and School of Biomolecular and Physical Sciences, Griffith University, Brisbane, Queensland 4111, Australia.
Abstract:
Thermodynamic integration, free energy perturbation, and slow change techniques have long been utilised in the calculation of free energy differences between two states of a system that has undergone some transformation. With the introduction of the Jarzynski equality and the Crooks relation, new approaches are possible. This paper investigates an important phenomenon - systems undergoing a change in volume/density - and derives both the Jarzynski equality and Crooks relation of such systems using a statistical mechanical approach. These results apply to systems with arbitrary particle interactions and densities. The application of this approach to the expansion/compression of particles confined within a vessel with a piston and within a periodic system is considered.
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