The potential energy of two atoms in a diatomic molecule is approximated by U(r)= a/r^12 - b/r^6, where r is the spacing between atoms and a and b are positive constants.

For the molecule CO, the equilibrium distance between the carbon and oxygen atoms is 1.13 X 10-0 m and the dissociation energy is 154 X 10-'8 I per molecule. Find the values of the constants a and b.n