Electronic spectroscopy of the Hg⎯Ar van der Waals complex was performed to determine the dissociation energy of the complex in the first excited state (Quayle, C. J. K. et al. Journal of Chemical Physics 99 (1993): 9608). As described in P25.6, the following data regarding ΔG versus n were obtained:

n____________________ ΔG (cm⁻¹)

1……………………………. 37.2

2……………………………. 34

3……………………………. 31.6

4……………………………. 29.2

5……………………………. 26.8

a. Construct a Birge–Sponer plot (ΔG versus n + 1/2) using the given data, and using a best fit to a straight line, determine the value of n where ΔG = 0. This is the vibrational quantum number at dissociation in the excited state. ΔG_1/2 can also be determined from the plot.

b. The area under the Birge–Sponer plot is equal to the dissociation energy, D₀ for this van der Waals complex in the excited state.The area can be determined by summing the ΔG values from n = 0 to n at dissociation [determined in part (a)]. You can also integrate the best-fit equation to determine D₀.