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$$
E^{hb}_{LJ}(r)=AR^{-12}-BR^{-10}cos^n\theta=4\epsilon\left\lbrace 5\left[ \frac{\sigma}{r}\right]^{12}-6\left[ \frac{\sigma}{r}\right]^{10}  \right\rbrace cos^n\theta
$$

$$
E^{hb}_{MORSE}(r)=D_0\left\lbrace \chi^2 - 2\chi\right\rbrace cos^n\theta=D_{0}\left\lbrace e^{- 2 \alpha (r - r_0)} - 2 e^{- \alpha (r - r_0)} \right\rbrace cos^n\theta
$$

$$
where \qquad r < r_c, \qquad cos^2\left( \theta\right) >  cos^2\left( \theta_c\right)
$$
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