8-6 Lennard-Jones potential

The 8-6 Lennard-Jones potential (also known as the 6-8 potential) is a variant the more well known Lennard-Jones model. It is particularly useful for computing non-bonded interactions. The potential is given by (Eq. 4 in):

$\Phi _{12}(r)=\epsilon \left[3\left({\frac {\sigma }{r}}\right)^{8}-4\left({\frac {\sigma }{r}}\right)^{6}\right]$

where

• $r:=|\mathbf {r} _{1}-\mathbf {r} _{2}|$
• $\Phi _{12}(r)$ is the intermolecular pair potential between two particles or sites
• $\sigma$ is the diameter (length), i.e. the value of $r$ at which $\Phi _{12}(r)=0$
• $\epsilon$ is the well depth (energy)