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X-ray Reflectivity Studies of Atomic-level Surface-segregation in a Liquid Eutectic Alloy of AuSn

Venkatachalapathy S. K. Balagurusamy·Reinhard Streitel·Oleg G. Shpyrko·P. S. Pershan·Mati Meron·Binhua Lin
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Abstract

X-ray reflectivity studies reveal atomic-level surface-segregation at the free surface of the eutectic Au71Sn29 liquid alloy. The surface-segregation extends up to three layers, in which the top layer is almost a pure monolayer of Sn, the second layer is almost a pure monolayer of Au and the third layer appears to be slightly enhanced in Au. Although the surface-segregation concentration profiles can be qualitatively accounted for by the theories of Defay-Prigogine and Strohl-King, they cannot satisfactorily account for the measured surface tension. PACS numbers: 61.20.-p, 61.10.-i, 68.03.-g

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Venkatachalapathy S. K. Balagurusamy, Reinhard Streitel, Oleg G. Shpyrko, P. S. Pershan, Mati Meron, Binhua Lin. 2007-02-08. X-ray Reflectivity Studies of Atomic-level Surface-segregation in a Liquid Eutectic Alloy of AuSn. https://arxiv.org/abs/cond-mat/0702193

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