The stability of gaseous nuclei at liquid-solid interfaces

A free energy analysis is used to investigate the stability of gas-vapor nuclei which are trapped in solid surface cavities. The cavities are axisymmetric but otherwise of arbitrary geometry. For a uniform temperature, it is shown that a pre-existing nucleus begins to grow spontaneously when the radius of curvature of the liquid-gas interface reaches a local minimum value. For a range of contact angles this condition implies that the liquid-gas interface is hemispherical. Results are presented for a cavity of specific geometry—the conical cavity.