Locating Li (2+) Energy Levels - eV

Click For Summary

Discussion Overview

The discussion revolves around locating the energy levels of the lithium ion Li (2+) in electron volts (eV). Participants explore various methods and resources for finding this information, touching on theoretical and practical aspects of quantum mechanics.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant requests information on the energy levels of Li (2+) and expresses difficulty in finding it in textbooks or online.
  • Another participant suggests a resource from the NIST website, although they express uncertainty about its usefulness.
  • A different participant proposes using quantum mechanical solutions to determine energy levels, mentioning the need to fill electron shells according to quantum numbers and the concept of excitation energy levels.
  • Another participant counters that calculating the energy levels is overly complex since they are well tabulated.
  • One participant states that Li (2+) behaves like a hydrogen-like ion, providing a formula for its energy levels, while noting that this formula neglects fine and hyperfine structure.

Areas of Agreement / Disagreement

Participants express differing views on the complexity of finding energy levels, with some advocating for theoretical calculations and others suggesting that tabulated values are sufficient. There is no consensus on the best approach to obtain the energy levels.

Contextual Notes

Some assumptions about the applicability of quantum mechanical solutions and the limitations of the provided formula are not fully explored, leaving open questions about accuracy and completeness.

Haftred
Messages
53
Reaction score
0
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.
 
Physics news on Phys.org
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
 
that's way too much work considering that the levels are well tabulated.
 
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:

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
0
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
1
Views
3K
Replies
1
Views
3K
  • · Replies 2 ·
Replies
2
Views
5K