Surface Free Energy of a Dilute Gas

抄録

The effect of boundary wall on a dilute gas of hard spheres is discussed. The free energy of the system is given as a function, not only of the volume, but also of the surface area of the container. The formula for the excess free energy due to the surface (surface tension) is given both for classical as well as for quantum mechanics. The quantum correction substitutes the effective diameter σ_eff for the classical diameter σ of a molecule.