I Relevance of the Rydberg Constant?


Homework Helper
Question about the Rydberg Constant.
Summary: Question about the Rydberg Constant.

The Rydberg constant is essentially a 'relic' of a now obsolete model (the Bohr model) of the Hydrogen atom. So my question is why do scientists keep trying to measure it to greater and greater degrees of precision?

Also I thought that the Rydberg constant / Rydberg energy would relate directly to accurately obtained values of atomic hydrogen ionization energy. But this does not seem to be the case. So what 'correction' needs to be applied to the Rydberg constant (adjusted for Hydrogen) such that it agrees with an accurately obtained value of ionization energy for the same atom ? Why do we keep it , if it is no longer directly reflective of the physical quantity it was designed to determine (via calculation of 1 - infinity transition) ?

RH = 109677.576 cm-1.
Ei(H) = 109678.7717426 (10) cm−1.

I know my RH is showing way less significant figures than for Ei(H) but the difference is already evident in the units column.

Formulations of the Dirac energy equation I have seen appear to depend only upon mc^2 and the fine structure constant although elsewhere it appears there are more complex versions which somehow 'reincorporate' the Rydberg constant. Why ?

Disclaimer: I have no idea what's going on in the Maths per above link - was just interested in the formula at the end of it!


Homework Helper
Thanks for the refs. I had a look.

I know about the use of the Rydberg formula in calculating spectral lines. Point is there is now a more accurate formula for calculating spectral lines. This formula doesn't seem to depend upon the Rydberg constant .

Don't know if small corrections such as for Lamb shift and/ or recoil energy rely on Rydberg constant ?

Want to reply to this thread?

"Relevance of the Rydberg Constant?" You must log in or register to reply here.

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving