Three Dimensional Nucleation

Abstract

The realization that phase changes, i.e. condensation of a vapor to its liquid or solid phase, boiling of a liquid, melting of a solid does not necessarily occur at equilibrium was published as early as 1724 by G. FAHRENHEIT.¹ J. T. LOWITZ in 1785 showed that acetic acid crystals are selective nuclei for the crystalization of acetic acid.¹ But it was not until 1926, when a paper by VOLMER and WEBER² was published, that a predictive equation for the rate of nucleation became available. Advances quickly followed. FARKAS,³ based on a suggestion by SZILLARD, provided a kinetic scheme for calculating the unknown constant. BECKER and DÖRING⁴ used this scheme but obtained the backward rate (this terminology will be explained later) from the Kelvin equation. ZELDOVICH suggested a continuum version. Many others have also made significant contributions. A very good review of much of the early history can be found in Volmer’s book. While this book is in some places difficult to read it is nevertheless highly recommended. Other sources are the three volume set edited by ZETTLEMOYER^6,7,8 and the book by ABRAHAM.⁹