Theory of spinodal decomposition assisted crystallization in binary mixtures
14 May 2010-Journal of Chemical Physics (American Institute of Physics)-Vol. 132, Iss: 18, pp 184908-184908
TL;DR: In this paper, the authors proposed a general theory of crystallization of one component from an unstable mixture of two components by addressing the coupling between the spinodal decomposition associated with concentration fluctuations in the mixture and the nucleation kinetics for the crystallization.
Abstract: We propose a general theory of crystallization of one component from an unstable mixture of two components by addressing the coupling between the spinodal decomposition associated with concentration fluctuations in the mixture and the nucleation kinetics for the crystallization. We propose that the domains created spontaneously by spinodal decomposition then present interfaces on which heterogeneous nucleation of the crystallizable component takes place with a much reduced nucleation barrier. Combining the theories of heterogeneous nucleation and spinodal decomposition kinetics, we present an analytic calculation of the nucleation rate as a function of the allowed duration of spinodal decomposition as well as the spinodal quench depth. In the present theory, shorter time evolution of spinodal decomposition or, equivalently, larger propensity of heterogeneous nucleation, results in faster crystallization. This is in contrast to the expectation of faster nucleation in more pure phases at later stages of spinodal decomposition. The analytic formula is found to correspond well with the recent experimental results on polymer mixtures for the late stage of spinodal decomposition kinetics. More detailed experiments are required to verify our prediction for the nucleation rate for early times and for different quench depths.
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References
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Book•
01 Jan 1972
TL;DR: The field of phase transitions and critical phenomena continues to be active in research, producing a steady stream of interesting and fruitful results as discussed by the authors, and the major aim of this serial is to provide review articles that can serve as standard references for research workers in the field.
Abstract: The field of phase transitions and critical phenomena continues to be active in research, producing a steady stream of interesting and fruitful results. It has moved into a central place in condensed matter studies. Statistical physics, and more specifically, the theory of transitions between states of matter, more or less defines what we know about 'everyday' matter and its transformations. The major aim of this serial is to provide review articles that can serve as standard references for research workers in the field, and for graduate students and others wishing to obtain reliable information on important recent developments.
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