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Crystals of Na+ ions at the surface of a silica hydrosol

Aleksey M. Tikhonov
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Abstract

I used x-ray grazing incidence diffraction to measure the spatial correlations between sodium ions adsorbed with Bjerrum's density at the surface of a monodispersed 22-nm-particle colloidal silica solution stabilized by NaOH with a total bulk concentration mol/L. My findings show that the surface compact layer is in a two-dimensional crystalline state (symmetry p2), with four ions forming the unit cell and a ~30 Angstrom translational correlation length between sodium ions.

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Aleksey M. Tikhonov. 2007-01-06. Crystals of Na+ ions at the surface of a silica hydrosol. https://doi.org/10.1063/1.2734542

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