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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
A systematic formulation of the virial expansion for nonadditive interaction potentials
1Institut für Chemie, Universität Rostock, Albert-Einstein-Strasse 3a, D-18059 Rostock, Germany. robert.hellmann@uni-rostock.de
The Journal of Chemical Physics
|September 8, 2011
Summary
A new method simplifies calculating virial coefficients for classical gases, even with complex interactions. This approach reduces the number of cluster diagrams needed for high-order calculations, making computations more efficient.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Physical Chemistry
Background:
- The virial expansion is crucial for describing non-ideal gas behavior.
- Calculating high-order virial coefficients is computationally intensive, especially for complex potentials.
Purpose of the Study:
- To develop a new formulation for virial expansion applicable to non-pairwise-additive potentials.
- To provide explicit expressions for virial coefficients up to the eighth order.
- To improve the computational efficiency of calculating high-order virial coefficients.
Main Methods:
- Derivation of a generalized virial expansion.
- Expression of virial coefficients as integrals over sums of cluster diagrams.
- Focus on moderate increase in cluster diagrams with increasing order.
Main Results:
- A novel formulation of virial expansion is presented.
- Explicit expressions for virial coefficients up to the eighth order are derived.
- The number of cluster diagrams grows more slowly compared to previous methods.
Conclusions:
- The new formulation is suitable for numerical evaluation.
- This method is particularly advantageous for computing high-order virial coefficients.
- It offers a more efficient pathway for theoretical and computational studies of classical gases.
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