where 𝑚 ⃗⃗⃗ 0 and 𝐴 are the zero-field transition dipole and the transition dipole polarizability, respectively. Importantly, measuring nitrile TDMs enables quantification of nitrile electric fields in H-bonding environments by using eq. 3a. In addition, jointly interpreting the nitrile's TDM and frequency using eq. 3a and eq. 2, respectively, enables quantification of the anomalous H-bonding blueshift ∆𝜈̅ 𝐻𝐵 . In our recent study, we measured nitrile frequencies and TDMs to directly assess nitrile H-bonding blueshifts for the first time. The new TDM-based method showed that ∆𝜈̅ 𝐻𝐵 can adopt values in a large range from 2 cm -1 to 22 cm -1 in distinct solvent or protein environments. Consequently, we wondered whether the blueshift's magnitude could be a useful metric to describe H-bonding, that is, if ∆𝜈̅ 𝐻𝐵 in eq. 2 could be mathematically modelled. Previous theoretical work explored the complicated vibrational behavior of the C≡N group and suggested that the anomalous 𝜈̅ /𝐹 ⃗ -trend stems from nonnegligible higher order multipole effects or from contributions due to Pauli repulsion. Further, previous work implied that ∆𝜈̅ 𝐻𝐵 may be a HB angle-dependent term (Fig. ), which would be consistent with both proposed physical origins. The lack of intuition for the blueshift's magnitude motivates the need to model ∆𝜈̅ 𝐻𝐵 in a physically interpretable form.