# Calculating binding energies for excitated levels in potassium?

Suppose a laser is used to excite electronic transitions in potassium from the $3p$ orbitals to ones higher than $4s$. When I attempt to use the Bohr model to calculate binding energies, what I obtain for $n\le4$ disagrees significantly with this source, calling into doubt my results for $n>4$. I think it might be possible to use the Rydberg formula, but I'm having trouble finding a working example that computes the right energies; in addition, there is another form, and the two seem inconsistent. How does one calculate the binding and transition energies in potassium for levels $n>4$? Are the quantum defects for arbitrary elements available online?

What changes here if we're talking not about pure potassium but potassium chloride?

• Perhaps relevant: chemistry.stackexchange.com/questions/32350/… Oct 25, 2015 at 11:41
• What do you expect by using the Victorian technology (Bohr model)? :) More than a century ago Bohr himself attempted to use his model to calculate energy levels in many-electron atoms and quickly found that it gives unacceptable numbers already for the lightest of then, $\ce{He}$ atom. For the next couple of decades after this discovery a scientific thought in that area had developed revolutionary and a good physical theory that gives way better predictions for atomic energy levels (amongst many other things) was formulated. Oct 26, 2015 at 21:41
• Fair enough. :) But my problem is a practical one, and it would be nice to have realistic transition energies, so that I will know what photon wavelengths are needed to excite the transitions. Any help is appreciated. Oct 26, 2015 at 22:26