Kirkwood-Buff Integrals for Finite Volumes
Peter Krüger1, Sondre K Schnell, Dick Bedeaux2
1†ICB, UMR 6303 CNRS, Université de Bourgogne, F-21078 Dijon, France.
The Journal of Physical Chemistry Letters
|August 19, 2015
Summary
Finite-volume Kirkwood-Buff (KB) integrals were derived for hyperspheres. This method provides accurate KB integral estimates for infinite systems and is suitable for molecular dynamics simulations.
Area of Science:
- Statistical mechanics
- Computational physics
Background:
- Kirkwood-Buff (KB) integrals are essential for understanding fluid thermodynamics and phase behavior.
- Calculating KB integrals for infinite systems traditionally poses computational challenges.
Purpose of the Study:
- To derive exact finite-volume expressions for Kirkwood-Buff integrals.
- To develop a more accurate and efficient method for estimating KB integrals for infinite systems.
- To demonstrate the applicability of this method to molecular dynamics simulations.
Main Methods:
- Derivation of exact finite-volume Kirkwood-Buff (KB) integral expressions for hyperspheres in 1, 2, and 3 dimensions.
- Analysis of the linear scaling of these integrals with inverse system size.
- Application to molecular dynamics simulations of closed systems to obtain KB integrals for open systems.
Main Results:
- Exact finite-volume KB integral expressions were obtained.
- Demonstrated linear scaling with inverse system size, enabling accurate extrapolation to infinite systems.
- Showed significantly improved convergence compared to traditional expressions.
- Validated the method for computing KB integrals from simulations of closed systems.
Conclusions:
- The derived finite-volume KB integral expressions offer a superior approach for accurate estimation in infinite systems.
- This method is highly suitable for computation using molecular dynamics simulations, efficiently yielding results for open systems from closed system simulations.
Keywords:
liquidsmixturesmolecular dynamics simulationpair correlation functionssmall systemsthermodynamic propertiesMore Related Videos
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