I Is this Lennard Jones potential image wrong on the Wikipedia Italian page?

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I found this image on the wikipedia italian page for the Lennard-Jones potential and I think the derivative displayed are wrong: not only in that reange (below r_eq) the negative derivative of the force should be negative and vice versa, but also the physcal meaning is that F(r) = - \frac{dU(r)}{dr} so I think that this is the derivative that should be displayed.
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eneacasucci said:
I found this image on the wikipedia italian page for the Lennard-Jones potential and I think the derivative displayed are wrong: not only in that reange (below r_eq) the negative derivative of the force should be negative and vice versa, but also the physcal meaning is that F(r) = - \frac{dU(r)}{dr} so I think that this is the derivative that should be displayed.
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I agree.

It would appear that ##- \frac {\partial F}{\partial r}## should be ##- \frac{dU} {dr} ##, which is the force, ##F(r)##.

(Since ##U(r)## is a function of ##r## only, I don’t think a partial derivative is appropriate.)

When ##F(r)>0## (for ##r<r_0##) we have repulsion.
When ##F(r)<0 ## (for ##r>r_0##) we have attraction.
 
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