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F. Summary Interactions

  • Page ID
    4670
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    Some programs assign charges using rules or templates, especially for macromolecules. In some force-fields, the torsional potential is calibrated to a particular charge calculation method (rarely made known to the user). Use of a different method can invalidated the force-field consistency. Sometimes, an additional bonded interaction term, improper dihedrals, are added as illustrated below. The potential for that is given by the following equation:

    Eimproper = Σangles kω (ω - ωo)2

    All of the potential energy functions are illustrated in the graph below, where V is the potential energy.

    pefunctions.gif

    Go to this great web site by Sharon Hammes-Schiffer, Shaffer Associate Professor of Chemistry Theoretical and Computational Chemistry at Penn State to see interactive graphs for these potential functions.


    F. Summary Interactions is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Henry Jakubowski.

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