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arXiv · cond-mat/9806148

Variable Curvature Slab Molecular Dynamics as a Method to Determine Surface Stress

Daniele Passerone·Erio Tosatti·Guido L. Chiarotti·Furio Ercolessi
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Abstract

A thin plate or slab, prepared so that opposite faces have different surface stresses, will bend as a result of the stress difference. We have developed a classical molecular dynamics (MD) formulation where (similar in spirit to constant-pressure MD) the curvature of the slab enters as an additional dynamical degree of freedom. The equations of motion of the atoms have been modified according to a variable metric, and an additional equation of motion for the curvature is introduced. We demonstrate the method to Au surfaces, both clean and covered with Pb adsorbates, using many-body glue potentials. Applications to stepped surfaces, deconstruction and other surface phenomena are under study.

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Daniele Passerone, Erio Tosatti, Guido L. Chiarotti, Furio Ercolessi. 1998-06-11. Variable Curvature Slab Molecular Dynamics as a Method to Determine Surface Stress. https://doi.org/10.1103/physrevb.59.7687

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