The Surface Diffusion Length of Water Molecules on Faceted Ice: A Reanalysis of “Roles of Surface/Volume Diffusion in the Growth Kinetics of Elementary Spiral Steps on Ice Basal Faces Grown from Water Vapor,” by Asakawa et al

نویسنده

  • Kenneth G. Libbrecht
چکیده

We reanalyzed the measurements made by Asakawa et al. [1] of the growth velocities of singlemolecule-high steps on basal ice surfaces, as we believe the authors made a number of incorrect assumptions regarding ice growth parameters and bulk diffusion in their experiments. Applying what we believe are more accurate assumptions, we used the data in [1] to derive a surface diffusion length of xs ≈ 10 nm for water molecules on basal ice surfaces at T = −8.4 C, about 500 times lower than what was reported in [1]. Moreover, in our analysis we found that no information about the height of the Ehrlich-Schwoebel barrier could be obtained from these measurements.

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تاریخ انتشار 2015