Buckingham potential

The Buckingham potential is a formula proposed by Richard Buckingham which describes the Pauli repulsion energy and van der Waals energy ${\displaystyle \Phi _{12}(r)}$ for the interaction of two atoms that are not directly bonded as a function of the interatomic distance ${\displaystyle r}$. It is a variety of interatomic potentials.

Here, ${\displaystyle A}$, ${\displaystyle B}$ and ${\displaystyle C}$ are constants. The two terms on the right-hand side constitute a repulsion and an attraction, because their first derivatives with respect to ${\displaystyle r}$ are negative and positive, respectively.

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