DiMasi, E.Tostmann, H.Shpyrko, O. G.Huber, P.Ocko, B. M.Pershan, PeterDeutsch, M.Berman, L. E.2010-09-012001DiMasi, E., H. Tostmann, O. G. Shpyrko, P. Huber, B. M. Ocko, Peter S. Pershan, M. Deutsch, and L. E. Berman. 2001. Pairing interactions and Gibbs adsorption at the liquid Bi-In surface: A resonant x-ray reflectivity study. Physical Review Letters 86(8): 1538-1541.0031-9007http://nrs.harvard.edu/urn-3:HUL.InstRepos:4419630Resonant x-ray reflectivity measurements from the surface of liquid Bi22In78 find only a modest surface Bi enhancement, with 35 at.% Bi in the first atomic layer. This is in contrast to the Gibbs adsorption in all liquid alloys studied to date, which show surface segregation of a complete monolayer of the low surface tension component. This suggests that surface adsorption in Bi-In is dominated by attractive interactions that increase the number of Bi-In neighbors at the surface. These are the first measurements in which resonant x-ray scattering has been used to quantify compositional changes induced at a liquid alloy surface.en-USJournal Article10.1103/PhysRevLett.86.1538