ABSTRACT
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 technology 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 available 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 1017. Reiss and coworkers [9,10] have argued that the Lothe and Pound correction factor was exaggerated too much due to the neglect of the ªuctuation of the center of mass of the nucleus and a new correction
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
was proposed to be a factor of 103-106. Recently Kusaka [11] has derived a rigorous formula for the correction factor within the framework of the Gibbs process of drop formation and calculated numerically this factor for the Lennard-Jones system. The calculated values ranged from 109 to 1013. The numerical calculation is probably the most direct way to determine the correction factor. However, the calculations of this kind are only possible for simple systems and, therefore, an analytical expression for the correction factor applicable to a wide range of real systems is necessary. In this paper the derivation of the analytical formula for the translation-rotation correction factor will be given.
