Classical Nucleation Theory - Aerosols: Measurement, Dosimetry, and Health Effects - page 503

19 Classical Nucleation Theory

Account of Dependence
of the Surface Tension on
Curvature and Translation-
Rotation Correction Factor

S.V. Vosel, A.A. Onischuk, P.A. Purtov, and T.G. Tolstikova

CONTENTS
19.1 Introduction .......................................................................................................................... 503
19.2 Homogeneous Nucleation from Supersaturated Vapor ........................................................ 504
19.3 Calculation of Zeldovich Factor ........................................................................................... 506
19.4 Translation-Rotation Correction Factor................................................................................ 509
19.5 Theory of Kusaka and Analytical Formula for the Correction Factor ................................. 512
19.6 Assembly of Drops: The Correction Factor for the Nucleation Rate ................................... 516
19.7 Comparison with the Kusaka's Numerical Simulation Results............................................ 517
19.8 Approximate Analytical Formula for the Nucleation Rate: Its Application
to the Estimation of Surface Tension of Critical Nucleus from the
Experimental Supersaturation Ratio and Nucleation Rate ................................................... 519
19.9 Conclusion ............................................................................................................................ 525
References...................................................................................................................................... 526

19.1 INTRODUCTION
Classical nucleation theory (CNT) developed by Volmer and Weber, Becker and Döring, Zeldovich,
and Frenkel [1] has been used extensively by specialists in different areas of science and technol-
ogy to calculate the rates of homogeneous nucleation from the supersaturated vapor. The theory
looks very attractive to many because it uses just the bulk physical-chemical parameters avail-
able in handbooks. However, numerous deviations of the theory predictions from the experimental
measurements were observed giving the difference in several orders of magnitude for water [2]
and organic substances [3,4] and tens of that for metals [5-7]. One of the sources of error in CNT
comes from the contribution of the translational-rotational degrees of freedom to the free energy
of critical nucleus. Due to this contribution the so-called free energy correction factor arises in
the formula for the nucleation rate. Lothe and Pound [8] have estimated (within the framework
of the Gibbs imaginary process of drop formation) the translational-rotational contribution to the
free energy of critical nucleus which gave the correction factor for water of about 10 17 . Reiss and
coworkers [9,10] have argued that the Lothe and Pound correction factor was exaggerated too
much due to the neglect of the luctuation of the center of mass of the nucleus and a new correction

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