X-ray synchrotron study of liquid-vapor interfaces at short length scales: effect of long-range forces and bending energies

Phys Rev Lett. 2003 May 30;90(21):216101. doi: 10.1103/PhysRevLett.90.216101. Epub 2003 May 27.

Abstract

We have investigated the small-scale structure of the liquid-vapor interface using synchrotron x-ray scattering for liquids with different molecular structures and interactions. The effective momentum-dependent surface energy first decreases from its macroscopic value due to the effect of long-range forces, and then increases with increasing wave vector. The results are analyzed using a recent density functional theory. The large wave-vector increase is attributed to a bending energy for which local and nonlocal contributions are equally important.