Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Two-Dimensional Hard Dumbbells. II. Pressure in Terms of Free Volumes and Surfaces



S Gay, James C. Rainwater, P D. Beale


For systems of fused-hard-sphere molecules, we relate cavity distributions to free-volume distributions and derive new statistical geometry relations between thermodynamic and cavity properties. From these results, we formulate two different approaches for calculating the pressure of systems of two-dimensional homonuclear hard dumbbells in terms of the geometry of the free volume of a molecule obsrved over the course of a simulation. We find a simple linear relationship to exist between the compressibility and the average of the ratio of the surface area and volume of the angle-averaged free volumes of the dumbbells. We find excellent agreement between the pressure as calculated via both approaches and the pressure as calculated from simulations.
Journal of Chemical Physics
No. 22


fused-hard-sphere molecules


Gay, S. , Rainwater, J. and Beale, P. (2000), Two-Dimensional Hard Dumbbells. II. Pressure in Terms of Free Volumes and Surfaces, Journal of Chemical Physics (Accessed February 24, 2024)
Created June 8, 2000, Updated February 17, 2017