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Molecular Mechanics and Dynamics Studies of Chemisorbed Monolayers of Alkanethiolates

Published online by Cambridge University Press:  01 January 1992

Yitzhak Shnidman ,
James E. Eilers ,
Abraham Ulman  and
Harrell Sellers
Yitzhak Shnidman
Affiliation:
Computational Science Laboratory, Eastman Kodak Company, Rochester, NY 14650
James E. Eilers
Affiliation:
Computational Science Laboratory, Eastman Kodak Company, Rochester, NY 14650
Abraham Ulman
Affiliation:
Corporate Research Laboratories, Eastman Kodak Company, Rochester, NY 14650
Harrell Sellers
Affiliation:
Department of Chemistry, South Dakota State University, Brookings, SD 57007
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Abstract

We study ordering within closely packed monolayers of thiol derivatives self-assembled on gold substrates by chemisorption from solution. We discuss constant stress molecular mechanics and dynamics simulations of alkanethiolate monolayers on Au(111) and Au(l00) surfaces. In the first case, we use the MM2 force field augmented with classical chemisorption parameters obtained from fitting to results of ab initioquantum mechanical calculations. In the second, the chemisorption to the Au(l00) surface was accomplished by using harmonic constraints to restrict the thiolate groups to the square lattice. It is shown that two chemisorption modes of alkanethiolate on Au(l11) exist, and that both give closely packed ordered monolayers. In the system on Au(100), rearrangement towards close-packing is achieved at the expense of distortions that increase the intrachain elastic energy.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 291: Symposium O – Materials Theory and Modeling , 1992 , 211
Copyright
Copyright © Materials Research Society 1993

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References

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