One model for the potential energy of a two-atom molecule, where the atoms are separated by a distance r, is U(r)=U0[(r0/r)13-(r0/r)9] where r0=0.85nm and U0=6.2eV. What is the distance between the atoms when the molecule is in stable equilibrium?
The Attempt at a Solution
I set U(r)=0 b/k it's stable equilibrium and solved for r which gave me r0 which is incorrect. Any ideas?