Electronic partition function for molecule with degeneracies

AI Thread Summary
The discussion revolves around calculating the electronic partition function for an atom with specified energy levels and degeneracies at 2000K. The user identifies the ground state and two excited states, noting their degeneracies and energy levels. There is confusion regarding the calculation of energy values for the excited states and the application of the equation E=hv. Participants clarify that the correct approach involves using the energy differences in the partition function equation and emphasize the importance of calculating the ratio of energy differences to kBT for accurate results. The final consensus suggests that the electronic partition function is likely equal to 3, pending proper calculations.
wiveykid
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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
 
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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.
 
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