lammps/doc/Eqs/pair_colloid_ss.tex

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\begin{eqnarray}
	U &=& \frac{A_{ss}}{36} \left[ \left( \frac{\sigma}{r}
	\right)^{12} - \left( \frac{ \sigma}{r} \right)^6 \right], ~~
	r < r_c \nonumber
\end{eqnarray}

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