Right, good.

To solve quantitatively, start with the energy levels, E

_{v}, of the Morse potential:

[tex]E(\nu)=(\nu+\frac{1}{2})\tilde{\nu}-(\nu+\frac{1}{2})^2\chi_e\tilde{\nu}[/tex]

The Birge Sponer plot is a plot of ΔE(ν+1

ν) as a function of ν+1. So using the expression above, you should be able to determine an expression for ΔE in terms of the various parameters. (Hint: put in ν+1 for ν in the above expression, and then subtract the one from the other to get ΔE). From this expression, you can use the slope of the B-S plot to determine χ

_{e} and etc.

If you are using Atkins, this is solved for you, but it's a quick and good exercise to show yourself. (Atkins uses G instead of E, at least my version does... but G becomes confusing with Gibbs energy so I don't really like that.)