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Published experimental data of metastable zone width (MSZW) for the crystallization of four different solutes
from their saturated solutions, determined as the maximum antisolvent content Δxmax, by addition of selected
antisolvents as a function of feeding rate RA using theoretical equations based on power law (PL) and classical
nucleation theory (CNT) are analyzed and trends of variations of the parameters of the equations and rela-
tionship between the parameters of the two approaches are discussed. With Δxmax taken in mole fraction of the
antisolvent, from the analysis of the Δxmax(RA) data for the different investigated systems the following con-
clusions may be drawn:
(1) The values of the parameters of the linear dependence of ln(Δxmax) on lnRA of the PL-based
approach and those of the parameters of the linear dependence of (Δxmax) 2 on lnRA of the
CNT-based approach are mutually related.
(2) The preexponential factor A of the CNT, associated with the frequency of attachment of solute
molecules with, and their detachment from, the growing three-dimensional nuclei, and their
solute–solution interfacial energy γeff mainly depend on the product fa2, where f is the number
of molecules or ions of solute per m3 in its saturated solution and a2 is the dimensionless sol-
vent–antisolvent interaction parameter. The sequence of variation of γeff is opposite to that of
the preexponential factor A.
(3) The observed trend of variation of the nucleation constant K calculated from the analysis of
antisolvent content Δxmax taken in mole fraction is similar to that of the A for different systems.
However, A ≫ K and the ratio A/K ≈ 106.
(4) The values of γeff obtained from the MSZW data of the investigated compounds
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