Electronic partition function for molecule with degeneracies

Click For Summary

Homework Help Overview

The problem involves calculating the electronic partition function for an atom with specified energy levels and degeneracies at a temperature of 2000K. The energy levels include a threefold degenerate ground state, a non-degenerate excited state, and another threefold degenerate excited state, with energies given in wavenumbers.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants discuss the identification of energy levels and degeneracies, with one participant attempting to formulate the electronic partition function. Questions arise regarding the application of energy equations and the significance of degeneracy in the context of the problem.

Discussion Status

Participants are actively exploring the relationship between energy levels and their corresponding wavenumbers. Some guidance has been provided regarding the use of energy equations, and there is a recognition of the need to calculate energy differences in relation to kBT. Multiple interpretations of the energy calculations are being considered.

Contextual Notes

There is uncertainty regarding the correct application of energy equations and the implications of degeneracy on the partition function. Participants express confusion about the energy values and their calculations, indicating a need for further clarification on these concepts.

wiveykid
Messages
3
Reaction score
0

Homework Statement


A atom had a threefold degenerate ground level, a non degenerate electronically excited level at 3500 cm^-1(setting the energy orgin as the ground electronic state energy of the atom ) and a threefold degenerate level at 4700 cm^-1 . Calculate the electronic partition function of this atom at 2000K


Homework Equations



qel= sumnation{i=0inf}[gel*exp[-(Ei-Ei-1)/(kbT)]]

The Attempt at a Solution



I see three levels in the problem
I believe, given the problem statement, that g0=3, g1=1 @3500cm-1, g2=3@4700cm-1

I came up with the equation
qel= 3+ 1*exp[-(E1-E0)/(kbT)] + 3*exp[-(E2-E1)/(kbT)]

T= 2000K, kb= Boltzmann constant ~1.38e-23

I am having trouble finding the energy values for each excited state. I am not sure if E=hv applies to this problem.

Also I am not too confident in the equation I found.

If anyone understands degeneracy, electronic partition functions or excited electronic stateI would greatly appreciate any help
 
Physics news on Phys.org
I would assume that you just use
E = h f
= h c / lambda
= hbar c k
, no? (I'm assuming that the inverse lengths that the problem specifies are wavenumbers of photons that would be emitted from the corresponding energy differences.)
 
yes I guess I can just multiply those numbers by c to get the excited state energies. Doing this it seems that all the exponentials go to zero because kbT is so small and c is so large. I guess the electronic partition function ends up being equal to 3
 
wiveykid said:
yes I guess I can just multiply those numbers by c to get the excited state energies. Doing this it seems that all the exponentials go to zero because kbT is so small and c is so large. I guess the electronic partition function ends up being equal to 3
There is more to the calculation than just kBT and c. Try calculating the value of \frac{\Delta E}{k_B T} for the two excited states.

wiveykid said:
I came up with the equation
qel= 3+ 1*exp[-(E1-E0)/(kbT)] + 3*exp[-(E2-E1)/(kbT)]
That's pretty much correct, except that it is E2-E0 in the final term.

I am having trouble finding the energy values for each excited state. I am not sure if E=hv applies to this problem.
Yes, it does.
 
Last edited:

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
6
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 12 ·
Replies
12
Views
1K
  • · Replies 1 ·
Replies
1
Views
5K