Curvature expansion of density profilesP.-M. König1, 2, P. Bryk3, K. Mecke4 and R. Roth1
1 Max-Planck-Institut für Metallforschung - Heisenbergstrasse 3 70569 Stuttgart, Germany
2 Institut für Theoretische und Angewandte Physik, Universität Stuttgart Pfaffenwaldring 57, 70569 Stuttgart, Germany
3 Department for the Modeling of Physico-Chemical Processes Maria Curie-Sklodowska University, 20-031 Lublin, Poland
4 Institut fuer Theoretische Physik, Universität Erlangen-Nürnberg Staudtstrasse 7, 91058 Erlangen, Germany
received 28 October 2004; accepted in final form 23 December 2004
published online 2 February 2005
We present a technique to calculate density profiles of a fluid close to a hard convex wall by arguing that its equilibrium density distribution depends only on the local curvatures of the wall. We perform a systematic expansion of the profile in powers of the curvatures and apply it to a hard-sphere fluid within the framework of density-functional theory (DFT). For large distances from the wall, the curvature expansion can be done analytically. Our approach can be generalized to systems with short-ranged fluid-fluid and wall-fluid interaction potentials, as long as intrinsic length scales remain small.
82.70.Dd - Colloids.
61.20.Gy - Theory and models of liquid structure.
61.20.Ja - Computer simulation of liquid structure.
© EDP Sciences 2005