Soft question on central field potential used to calculate the wavefunction

[Zihan-Asd]

Dear Nikola,

Hi, I read your paper and some of your code on calculating the wavefunction to calculate things like <n|r|m>. You seemed to have used a central field potential with parameters determined by experiments for each kind of atom. I think this should be accurate enough for Rydberg atoms and not enough for low-lying states. Transitions between low-lying states can be determined by experiments and hence do not require direct calculations of wavefunctions. However, transitions from low-lying states to Rydberg states seem to need those calculations that are not accurate at low-lying states. So do you think the results are accurate enough in such situations?

Also, I came across a few papers using Hatree-Fock models and Many-body perturbation theory to do the similar calculations and it seems that this approach is more accurate and of course more complicated. However, do you think such method is necessary to bring the accuracy of calculating <n|r|m> when n is small and m is huge?

This is simply a soft question. Thank you for your time.

Zihan

[nikolasibalic]

Hi Zihan,

Thank you for the note. Indeed, the dipole matrix elements between low lying and high lying states are not ideally calculated with the current method, as you note. Is it good enough? That depends really on application, you have to try and check with experiments probably. We do know that for some atomic species, notably Cs, there are important discrepancies as noted in #51

Ideally, one would use this package to get low laying states wavefunctions. Incorporating these in ARC would be the best way to improve accuracy, however I haven't had enough time to investing interfacing that FORTRAN package with ARC.

I hope this helps. If you would like to contribute some improvements to these calculations, it would be great!

Best wishes,
Nikola

[Zihan-Asd]

Hi Nikola,

Thanks for your reply and reference. I am indeed a bit interested in learning and using the CI-MBPT method. However, it might take a long time. (Besides, I have other things on my plate as well..) If my procrastination does not prevent me from making progress in doing so, I would love to contribute.

Best,
Zihan