OPLS

The OPLS (Optimized Potentials for Liquid Simulations) force field was developed by Prof. William L. Jorgensen at Purdue University and later at Yale University.

The functional form of the OPLS force field is very similar to that of AMBER:

${\displaystyle E\left(r^{N}\right)=E_{\mathrm {bonds} }+E_{\mathrm {angles} }+E_{\mathrm {dihedrals} }+E_{\mathrm {nonbonded} }}$

${\displaystyle E_{\mathrm {bonds} }=\sum _{\mathrm {bonds} }K_{r}(r-r_{0})^{2}\,}$

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