Hard sphere model
The hard sphere (HS) interaction potential is given by
where is the potential energy between two spheres at a distance Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle r} , and is the sphere diameter.
HS Fluid: Equation of State (EoS); See Carnahan-Starling (three dimensions)
Related systems are:
Hard disks in a 2-dimensional space
Hard Rods in one dimension