Hard sphere model
The hard sphere (HS) interaction potential is given by
where Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle V\left(r\right)} is the potential energy between two spheres at a distance , and is the sphere diameter.
HS Fluid: Equation of State (EoS); See Carnahan-Starling