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Molecular Dynamics of Polyatomic Systems

  • J. P. Ryckaert
Chapter
Part of the NATO ASI Series book series (NSSE, volume 205)

Abstract

This paper is concerned with the application of Molecular Dynamics (MD) computer simulations to polyatomic molecules characterized by a mixing of “soft” (thermally activated) and “hard” (thermally inactivated) intramolecular modes. Statistical mechanics of these complex mechanical bodies will be reviewed in some detail, both for models treating the hard degrees by stiff springs and those which freeze them from the outset by geometrical constraints. Often, within the class of molecules investigated here, one or a few ‘soft’ coordinates control large conformational changes, implying the passage over a potential barrier of a few kT: within the MD approach, an accurate estimation of the internal distribution of such a “reaction coordinate” requires special techniques which force the system to sample the saddle point regions. In the context of polyatomic systems with or without geometrical constraints, the advantages of the MD technique working in cartesian coordinates over other techniques will be discussed.

Keywords

Polyatomic Molecule Stiff Spring Intermolecular Potential Holonomic Constraint Polyatomic System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 1991

Authors and Affiliations

  • J. P. Ryckaert
    • 1
  1. 1.Pool de Physique, CP223Université Libre de BruxellesBrusselsBelgium

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