On homogeneous nucleation theories from the vapor phase

Özet

Homogeneous nucleation theories from the vapor phase are revisited and recent semi-phenomenological models [1,2] based on Fisher's droplet model [3] for the Gibbs free energy of formation of a cluster are discussed. These models allow for the variation of surface tension with cluster size in addition to the contribution from translational, rotational, vibrational and configurational degrees of freedom of clusters. The resulting steady-state nucleation rate equations are derived and compared with expansion and diffusion cloud chamber experiments for a variety of substances (water, methanol, n-nonane, etc.). An overall good agreement is achieved for the range of temperatures investigated in contrast to comprasion with the classical Becker-Döring-Z'eldovich-Frenkel theory.