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arXiv · 1409.5562

A Two-parameter Extension of Classical Nucleation Theory

James F. Lutsko·Miguel A. Durán-Olivencia
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Abstract

A two-variable stochastic model for diffusion-limited nucleation is developed using a formalism derived from fluctuating hydrodynamics. The model is a direct generalization of the standard Classical Nucleation Theory. The nucleation rate and pathway are calculated in the weak-noise approximation and are shown to be in good agreement with direct numerical simulations for the weak-solution/strong-solution transition in globular proteins. We find that Classical Nucleation Theory underestimates the time needed for the formation of a critical cluster by two orders of magnitude and that this discrepancy is due to the more complex dynamics of the two variable model and not, as often is assumed, a result of errors in the estimation of the free energy barrier.

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James F. Lutsko, Miguel A. Durán-Olivencia. 2014-09-19. A Two-parameter Extension of Classical Nucleation Theory. https://doi.org/10.1088/0953-8984%2F27%2F23%2F235101

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