1. The problem statement, all variables and given/known data I need to calculate the work donde by the Lennard-Jones Law, considering: F(r)=F0 [2(σ/r)13-(σ/r)7] when approximating two atoms from infinity to the equilibrium position between both atoms 2. Relevant equations First thing I don't know how to calculate is the equilibrium position (x0) between two arbitrary atoms 3. The attempt at a solution I just integrated this force, considering WAB=∫F⋅dr ; r=A to r=B As I don't know the x0, I just integrate from A to B, to later analyze the result. Assuming A=-∞ and B=x0 W= ∫ F0 [2(σ/r)13-(σ/r)7] dr ; r=A to r=B = integrating... = 2F0σ13 ( r-12 /-12) - F0σ7 (r-6/-6) ; still need to evaluate Considering that A=-∞, I finally obtain: W= F0σ7/6 (1/x06)-F0σ13/6(1/x012) Is it right until here?