1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

A Spectrum

  1. Apr 23, 2005 #1
    Where can I find the different energy levels (in eV) for Li (2+). I can't seem to find it in my textbook or on the internet.
  2. jcsd
  3. Apr 24, 2005 #2


    User Avatar
    Science Advisor

  4. Apr 25, 2005 #3
    You could try quantum mechanic solutions ... not for the faint hearted though...
    If you know the number of electrons in Li you have to begin filling shells using the quantum numbers n,l and Ml .. which each have restrictions in their values. You keep filling the electrons in the shells (dont forget spins!) until you are left with an unfilled shell. Excitation energy levels occur when the last electron is placed in the higher energy levels and not the next available level.
    Have fun
  5. Apr 25, 2005 #4
    that's way too much work considering that the levels are well tabulated.
  6. Apr 25, 2005 #5


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Li2+ is just a hydrogen-like ion, I believe, so its energy levels are given simply by:

    [tex]E=13.6\frac{Z^2}{n^2}\ eV=\frac{122.4}{n^2}\ eV[/tex]

    This isn't exact because it neglects fine structure and hyperfine structure, but for most purposes, the above should suffice.
    Last edited: Apr 25, 2005
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: A Spectrum
  1. Absorption spectrum (Replies: 4)

  2. What is spectrum? (Replies: 1)

  3. Emission Spectrum (Replies: 17)