Homogeneous nucleation heteromolecular

Homogeneous nucleation is the formation of the condensed phase (particles) from purely gaseous molecules. If only a single molecular species is involved, the process is termed homomolecular, while it is called heteromolecular when more than one such species participates. Aspects of homogeneous nucleation depend to a great extent upon collision rates this leads to highly mixed results upon treatment by kinetic theoretic means. Undoubtedly, any ultimate description will necessitate details not only of kinetics but also of dynamics and microparticle microphysics to account for the rates and structure of critical (i.e., stable) cluster formation. 

It appears feasible to analyze the homogeneous nucleation process by molecular dynamics for molecules with spherically symmetric potentials, but the next step-extension to nonsymmetric potentials —appears to be almost prohibitive at present. The much more important nucleation processes-heteromolecular nucleation and heterogeneous nucleation, for example-must still be approached by phenomenological theories. 

Nucleation processes, especially in nature, are rarely homomolecular and homogeneous usually two species are involved (binary heteromolecular nucleation), and foreign surfaces may also be present (heterogeneous... 

Homogeneous-heteromolecular. self-nucleation of two or more species. No foreign nuclei or surfaces involved. 

We have seen that in homogeneous-homomolecular nucleation, nucleation does not occur unless the vapor phase is supersaturated with respect to the species. When two or more vapor species are present, neither of which is supersaturated, nucleation can still take place as long as the participating vapor species are supersaturated with respect to a liquid solution droplet. Thus heteromolecular nucleation can occur when a mixture of vapors is subsaturated with respect to the pure substances as long as there is supersaturation with respect to a solution of these substances. The theory of homogeneous-heteromolecular nucleation parallels that of homogeneous-homomolecular nucleation extended to include two or more... 

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