Enhanced wavelength-dependent surface tension of liquid-vapour interfaces
Max-Planck-Institut für Intelligente Systeme - Heisenbergstraße 3, 70569 Stuttgart, Germany, and IV. Institut für Theoretische Physik, Universität Stuttgart - Pfaffenwaldring 57, 70569 Stuttgart, Germany
Received: 1 December 2014
Accepted: 2 February 2015
Due to the simultaneous presence of bulk-like and interfacial fluctuations the understanding of the structure of liquid-vapour interfaces poses a long-lasting and ongoing challenge for experiments, theory, and simulations. We provide a new analysis of this topic by combining high-quality simulation data for Lennard-Jones fluids with an unambiguous definition of the wave-number–dependent surface tension based on the two-point correlation function of the fluid. Upon raising the temperature, develops a maximum at short wavelengths. We compare these results with predictions from density functional theory. Our analysis has repercussions for the interpretation of grazing-incidence small-angle X-ray scattering (GISAXS) at liquid interfaces.
PACS: 68.03.Hj – Liquid surface structure: measurements and simulations / 61.20.Ja – Computer simulation of liquid structure / 05.10.-a – Computational methods in statistical physics and nonlinear dynamics
© EPLA, 2015