Inert gas scattering from molten metals: Probing the stiffness and roughness of the surfaces of atomic liquids.

The surface rigidity and corrugation of the liquid metals indium, gallium, and bismuth are investigated by scattering neon, argon, and xenon from each liquid. The inert gas fractional energy transfers and trapping–desorption fractions are much lower for these atomic liquids than for molecular fluids, reflecting the high mass densities and high surface tensions of the liquid metals. The peak energy transfer at a 55° specular angle can be predicted by using hard sphere collision mechanics and by estimating the mass ratio μ=mgas/msurf by (0.28±0.02 Å-1) (ρgas/ρliq), where ρgas is the mass per cross-sectional area of the gas atom and ρliq is the bulk metal density. The specular scattering intensity decreases as the liquid’s temperature increases at a fractional rate approximately equal to -1/(2Tliq). The intensity appears to scale nearly inversely with the amplitude of the surface atom fluctuations. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]