Re: Energy level diagrams

[John Denker <jsd@AV8N.COM>]

carl preske wrote:
> A question came up on another list serve and the writer would like to
> know why the energy levels are lettered.  I know why the numbers are
> used for hydrogen but who set up the lettering scheme.

s,p,d,f stand for sharp, principal, diffuse, fundamental.
The names (and abbreviations) come from the earliest work
in spectroscopy -- any effort to sort out the various
spectral lines, long before there was any understanding
of atomic structure.

  http://www.google.com/search?q=sharp+principal+diffuse
  http://w3.msi.vxu.se/~pku/Rydberg/LifeWork.html