Tostmann H, DiMasi E, Shpyrko OG, Pershan PS, Ocko BM, Deutsch M
Division of Applied Sciences and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Phys Rev Lett. 2000 May 8;84(19):4385-8. doi: 10.1103/PhysRevLett.84.4385.
X-ray reflectivity measurements of the binary liquid Ga-Bi alloy reveal a dramatically different surface structure above and below the monotectic temperature T(mono) = 222 degrees C. A Gibbs-adsorbed Bi monolayer resides at the surface in both regimes. However, a 30 A thick, Bi-rich wetting film intrudes between the Bi monolayer and the Ga-rich bulk for T>T(mono). The wetting film's internal structure, not hitherto measured, is determined with A resolution, showing a concentration gradient not predicted by theory and a highly diffuse interface with the bulk phase.
二元液态镓铋合金的X射线反射率测量结果表明，在单熔温度T(mono)=222℃上下，其表面结构存在显著差异。在这两种情况下，表面均存在一层吉布斯吸附的铋单分子层。然而，当T>T(mono)时，一层30埃厚的富铋润湿膜侵入铋单分子层与富镓本体之间。此前未测量过的润湿膜内部结构，以高分辨率确定，显示出理论未预测到的浓度梯度以及与本体相高度弥散的界面。
