How to Write a Canonical Ensemble for a System Using the Einstein Model

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Homework Help Overview

The discussion revolves around setting up a canonical ensemble using the Einstein model for a system with a specified energy expression. Participants are exploring the formulation of the partition function in this context.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the definition of the partition function and its relation to the energy expression provided. There are attempts to clarify the correct notation and the implications of quantum statistics versus classical approaches.

Discussion Status

The discussion is active, with participants providing insights and corrections regarding the energy notation and the appropriate statistical framework. There is a focus on how to properly express the partition function, with some participants questioning the setup due to differing upper limits in the summations.

Contextual Notes

There are indications of confusion regarding the integration process and the treatment of the energy terms in the partition function. Participants are also navigating the differences between classical and quantum statistical mechanics.

romeo6
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Hi there,

I have a system with the following energy using the einstein model:

[tex]E_\nu=\sum_{i=1}^{2N} h\omega n_i+\sum_{j=1}^{N} h\omega n_j[/tex]
I need to set up a canonical ensemble for this.

How would I write the partition function please?
 
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Isn't the partition function defined as

[tex]\int \frac{d^{3N}p d^{3N}q}{N! h^{3N}} e^{-\beta H(p,q)}[/tex]

for [tex]N[/tex] particles. You just need to substitute for the energy that you have and perform the integration (hint integrate over all the freuqncies [tex]\omega[/tex] and you should only have to do one and simplify).
 
First, it't [itex]\hbar[/itex] instead of "h" in E_{\nu}. Second, this looks like an application of quantum statistics, and so the classical partition function won't be of any use.

Daniel.
 
Thanks, I think my problem is that I don't know how to set this up as thesummations have different upper values.

I want to write something like:

[tex]Q=\sum_{i=1}^{2N} e^{-\beta \hbar n_i}+\sum_{j=1}^N e^{-\beta \hbar n_j}[/tex]

where Q is the partition function.

Does this look anything like the partition function?
 

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