1. Sep 27, 2011

### kottur

1. The problem statement, all variables and given/known data

Consider a CO2 molecule, which is linear and has vibrational modes with frequency
corresponding to 2565 cm-1 (an asymmetric stretch), 1480 cm-1 (a symmetric stretch)
526 cm-1 (bends). Sketch a curve showing how the constant volume heat capacity of CO2
gas varies with temperature and mark the values of plateaus. (Recall: the spacing between
rotational levels is smaller than the spacing between the vibrational levels).

3. The attempt at a solution

I think Z=$\frac{1}{1-e^{-h\varpi/\tau}}$ but after that I have problems with finding U so that I can find the heat capacity with: C$_{v}$=$\left(\frac{dU}{d\tau}\right)_{v}$