On the other hand, as r increases, the potential energy does not increase without limit; it must approach asymptotically a finite value, the dissociation energy.
Then, you look up in a relatively small table the dissociation energies of all bonds broken and all bonds formed.
The dissociation energy for a C-C bond is 3.6 eV.
One result attracted particular attention: the calculated dissociation energy disagreed with the best experimental data then available, from Gerhard Herzberg's group.
Thus the extrapolation can be inaccurate and only an upper limit for the value of the dissociation energy can be obtained.
The dissociation energy of the ion is 1.8 eV.
This will always be greater than the dissociation energy of the complex.
This bond has a predicted dissociation energy of 62 kcal mol and is approximately as strong as those found among metal-halide bonds.
With up to 13 adjustable parameters they obtained a result very close to the experimental result for the dissociation energy.
The dissociation energy of the bond can be calculated by subtracting the zero point energy from the depth of the well.