## Dust formation in stellar winds## VII. Kinetic nucleation theory for chemical non-equilibrium in the gas phase
^{1} Technische Universität Berlin, Institut für
Astronomie und Astrophysik, PN 8-1, Hardenbergstr. 36, D-10623 Berlin,
Germany^{2} Max-Planck-Institut für Radioastronomie, Auf dem
Hügel 69, D-53121 Bonn, Germany
We present a new theoretical formulation of the nucleation process of solid particles from the gas phase with special emphasis on the effects of chemical non-equilibrium in the gas phase and thermal non-equilibrium between the gas and the clusters or dust grains. In the derivation of the nucleation rates from kinetic theory and from thermodynamic arguments thermal and chemical non-equilibrium are straightforwardly included. A hierarchy of expressions for the stationary nucleation rate is given, ranging from a system of equations, which determines the rate, to an approximate analytic expression in the case of a single dominating growth species, which requires only the time scales of the growth processes and the Gibb's free energy change for the formation of clusters.
This article contains no SIMBAD objects. ## Contents- 1. Introduction
- 2. The master equation in the case of chemical and thermal non-equilibrium
- 3. The stationary nucleation rate for chemical and thermal non-equilibrium
- 4. Summary
- Acknowledgements
- Appendix A: on the supersaturation ratio of
*N*-clusters - Appendix B: definition of the generalized departure coefficients
- References
© European Southern Observatory (ESO) 1998 Online publication: August 27, 1998 |