Changing the variable of integration to the inverse radius yields the integral φ φ = φ φ 0 + ∫ ∫ u d u 2 m L 2 E t o t − − 2 m L 2 U ( 1 / u ) − − u 2 which expresses the above constants C = 2 mE tot / L and G (u) = 2 mU (1/ u)/ L above in terms of the total energy E tot and the potential energy U (r).