Fig. 2: Gypsum nucleation experiments.
From: Gypsum heterogenous nucleation pathways regulated by surface functional groups and hydrophobicity
A Schematic illustration of gypsum nucleation experiments. B The representative number density of gypsum crystallites versus time for various saturation index (σ) values on surfaces terminated with −OH. The slopes of lines for each supersaturation value represent the steady-state nucleation rate, J0. Similar plots for surfaces terminated with −COOH, −NH2, −CH3, −SO3, and hybrid of NH2 and COOH groups are shown in Supplementary Fig. 4. C Gypsum nucleation rates obey classical nucleation theory; the linear relationship is predicted by Eq. 6 for all surfaces. The slope of the plots, B, represents the substrate-specific thermodynamic barrier to nucleation and is used to estimate gypsum–substrate interfacial free energy, γcs. D The total cluster ions near the surfaces (i.e., the distance between the center of mass (COM) of cluster minus the cluster radius and the surface groups is less than 15 Å) terminated with different functional groups as obtained from the MD simulations. Error bars are derived from the standard deviation of the average values calculated over the last 5 ns.
