Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 26 August 1994:
Vol. 265. no. 5176, pp. 1209 - 1212
DOI: 10.1126/science.265.5176.1209
Prev | Table of Contents | Next

Articles

Molecular Origins of Friction: The Force on Adsorbed Layers

Marek Cieplak 1, Elizabeth D. Smith 1, and Mark O. Robbins 1

1 Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA.

Simulations and perturbation theory are used to study the molecular origins of friction in an ideal model system, a layer of adsorbed molecules sliding over a substrate. These calculations reproduce several surprising features of experimental results. In most cases, the frictional force on a solid monolayer has a different form from that observed between macroscopic solids. No threshold force or static friction is needed to initiate sliding; instead, the velocity is proportional to the force. As in experiments, incommensurate solid layers actually slide more readily than fluid layers. A comparison of experiment, simulation, and analytic results shows that dissipation arises from anharmonic coupling between phonon modes and substrate-induced deformations in the adsorbate.

Submitted on March 22, 1994
Accepted on July 11, 1994


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Nanoscale Friction Varied by Isotopic Shifting of Surface Vibrational Frequencies.
R. J. Cannara, M. J. Brukman, K. Cimatu, A. V. Sumant, S. Baldelli, and R. W. Carpick (2007)
Science 318, 780-783
   Abstract »    Full Text »    PDF »
Molecular Mechanisms for the Functionality of Lubricant Additives.
N. J. Mosey, M. H. Muser, and T. K. Woo (2005)
Science 307, 1612-1615
   Abstract »    Full Text »    PDF »
Microscopic View of Structural Phase Transitions Induced by Shock Waves.
K. Kadau, T. C. Germann, P. S. Lomdahl, and B. L. Holian (2002)
Science 296, 1681-1684
   Abstract »    Full Text »    PDF »
Adsorbed Layers and the Origin of Static Friction.
G. He, M. H. Müser, and M. O. Robbins (1999)
Science 284, 1650-1652
   Abstract »    Full Text »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)