Dust formation in stellar winds: VII. Kinetic nucleation theory for chemical non-equilibrium in the gas phase

A.B.C. Patzer, A. Gauger, E. Sedlmayr

Astronomy & Astrophysics, 337, 847-858 (1998)

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Abstract:

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.