In order to experimentally test the possibility of multiple underlying and exchanging populations, we acquired an FTIR spectrum for F92oCNF at 100 K in frozen solution (Figure ). We also acquired a low-temperature spectrum for F62oCNF (Figure ) as a control since the room temperature IR TDM analysis revealed the nitrile is entirely non-H-bonding, consistent with the MD simulations (Table ). As predicted, F62oCNF's spectrum remains as a single band (central frequency of 2230.8 cm -1 ; Figure ; Table ). In contrast, F92oCNF's spectrum displays one dominant peak at 2246.9 cm -1 with a well-resolved shoulder centered at 2230.1 cm -1 (Figure ; Table ). By comparing F62oCNF's frequency with the frequency of F92oCNF's bluer band, it is clear this F92oCNF population must be H-bonding to attain such a transition energy. Additionally, the similarity of F92oCNF's shoulder frequency to F62oCNF's frequency coupled with the MD results suggests that the shoulder represents a non-Hbonding population. Low-temperature IR spectra were also obtained for F28oCNF and F96oCNF (Figure ). Like F92oCNF, those nitriles demonstrated bandshapes indicative of multiple populations, though band �itting was not as straightforward as in F92oCNF's case. Ultimately, the presence of multiple species at low-temperature for F28oCNF, F92oCNF, and F96oCNF (but not F62oCNF) together with the above exchange rate analysis provides strong evidence that the difference in the MD electric �ield distributions and the room temperature IR arises from rapid chemical exchange between H-bonding and non-Hbonding nitrile populations. What is more, since the transition energy for exchanging populations appears at the population-weighted value, our �indings also imply that the MD H-bonding/non-H-bonding median FC≡N,MD's should be averaged for comparison with FC≡N,TDM's.