The Boltzmann distribution of uniformly spaced energy levels

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SUMMARY

The discussion focuses on calculating the fraction of particles in the ground state of a system with uniformly spaced energy levels, specifically at a temperature of 300K using the Boltzmann distribution. The energy levels are defined as 3.2x10^-10 J apart, and the user initially miscalculated the energy states and the probability function due to missing minus signs in the Boltzmann equation. The corrected approach emphasizes the importance of accurately applying the Boltzmann distribution formula to avoid negative probabilities.

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corr0105
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The question states:
A system has energy levels uniformly spaced at 3.2x10^-10 J apart. Thepopulations of the energy levels are given by the Boltzmann distribution. What fraction of particles is in the ground state at T=300K.

I know that the Boltzmann distribution is:
_{}p*j=probability that a particle is in state j
=exp(-_{}Ej/KT) / \sumexp(-_{}Ej/KT)

I created my own expression for the energy state Ej:
_{}Ej=3.2x10^-20(j-1)
My thought process behind this was that to get the energy state of each level you have to multiply by the space between each level times 1 minus the level. In other words, E1=0*3.2x10^-20, E2=1(3.2x10^-10)...etc.

I set this pj* equal to: # particles in ground state (g) / # states (t)
Assuming that the particles in the ground state would have energy E=0 I plugged all of the given values into the equation: T=300, Ej=0, K=boltzmann's constant. Because the problem did not give the number of states my answer is in terms of t. I got an answer of:
-0.25875/(1+t)
Obviously this is wrong because you cannot have a negative number of particles.


ANY IDEA WHAT I'VE DONE WRONG?
thanks in advance for any help
 
Last edited:
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Your Boltzmann distribution function has a couple of minus signs missing.
 
I'm sorry, you are correct. The post has been edited. It was a typo, but the answer I got still stands.
 

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