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LB2

This keyword specifies the potential[18,19,20]

V = $\displaystyle {\frac{{\epsilon}}{{2}}}$$\displaystyle \sum_{{i<j}}^{}$$\displaystyle \left[\vphantom{ \left(\frac{r_{ij}}{\sigma}\right)^2+ \left(\frac{\sigma}{r_{ij}}\right)^2 }\right.$$\displaystyle \left(\vphantom{\frac{r_{ij}}{\sigma}}\right.$$\displaystyle {\frac{{r_{ij}}}{{\sigma}}}$$\displaystyle \left.\vphantom{\frac{r_{ij}}{\sigma}}\right)^{2}_{}$ + $\displaystyle \left(\vphantom{\frac{\sigma}{r_{ij}}}\right.$$\displaystyle {\frac{{\sigma}}{{r_{ij}}}}$$\displaystyle \left.\vphantom{\frac{\sigma}{r_{ij}}}\right)^{2}_{}$$\displaystyle \left.\vphantom{ \left(\frac{r_{ij}}{\sigma}\right)^2+ \left(\frac{\sigma}{r_{ij}}\right)^2 }\right]$, (10)

where ε and σ are set to unity.