X-ray reflectivity studies of the surface structure of liquid metals

doi:10.1016/0921-4526(95)00935-3

Physica B: Condensed Matter

Volume 221, Issues 1–4, 2 April 1996, Pages 257-260

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Abstract

Extensive theoretical predictions of atomic layering at the surfaces of liquid metals have remained unconfirmed due to the limited range of wave vector transfer q_z that has been previously measured. We report here on X-ray reflectivity studies from the surfaces of liquid mercury to q_z ≳ 2.8 Å⁻¹, and gallium to q_z ≳ 3.0 Å⁻¹, that show peaks which clearly demonstrate atomic layering with spacing on the order of the atomic diameter. The exponential decay of layer penetration into the bulk for Ga (6.5 Å) is larger than for Hg (3–3.5 Å). The prominent features of the layering remain unchanged under self-assembled monolayers of thiols. The Ga layering shows an unexpected strong temperature dependence. Differences between the reflectivity from Ga and Hg at small q_z indicate fundamental differences in the surface structure for these two liquid metals.

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¹: Present address: Department of Physics and Astronomy, University of Massachusetts, Amherst, MA 01003, USA.

²: Present address: Department of Physics, Ajou University, Suwon 442-749, South Korea.

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X-ray reflectivity studies of the surface structure of liquid metals

Abstract

Phys. Rev. B

Phys. Rev. A

Phys. Rev. B

Molecular Phys.

J. Phys.: Condens. Matter

Surf. Sci.

Phys. Rev. B.

J. Electrochem. Soc.

Science

Phys. Rev. Lett.