In order to find an empirical relation for the HB shift, we chose a DFT-based strategy in which individual positive point charges (125 cases; Fig. ) or individual water or methanol molecules (420 cases each; Fig. ) were placed around oTN's C≡N to model attractive purely electrostatic interactions or H-bonding interactions, respectively. These poses were optimized and normal mode analysis was performed to extract nitrile frequencies and TDMs (b3lyp/6-311++g** level of theory with GD3 dispersion correction). oTN was chosen as our model molecule because it is the sidechain fragment of the nonnatural amino acid o-cyanophenylalanine (oCNF), with which we previously developed and applied the new TDM-based analysis in solvent and protein environments. The charges and molecules were positioned at NC≡N-charge or NC≡N-OHB donor distances (d), respectively, ranging from 5.0 -8.0 Å for point charges and 2.5 -5.0 Å for HB donors, and C≡N-charge and C≡N-OHB donor angles (θ) of 70 -175° were used (Fig. ). The HB distance range was motivated by typical radial distribution functions of HBs, which have a first solvation sphere centered around 2.5 -3.5 Å. The angle range encapsulates HBs which vary from head-on (~ 180°) to sideon (~ 90°). Note that the ideal head-on angle of 180° was not used due to convergence issues in the DFT calculations. The DFT-derived vibrational frequencies (𝜈̅ ) and TDM magnitudes (|𝑚 ⃗⃗⃗|) were scaled by 0.9598 56 or 0.4464, respectively, to match the experimental zero-field observables (see Methods Section). Using DFT, we obtained |𝑚 ⃗⃗⃗| and 𝜈̅ values for oTN of 0.037 -0.060 D and 2210 -2255 cm -1 , respectively (see xaxes in Fig. ), which are consistent with prior experimental observations for aromatic nitriles (see Fig. ). From the observed ranges it can be seen that purely electrostatic and H-bonding environments give rise to similar values for |𝑚 ⃗⃗⃗| (Fig. ), consistent with eq. 3a's indication that |𝑚 ⃗⃗⃗| is only a function of 𝐹 ⃗ . For the frequencies (Fig. ), purely electrostatic perturbations produce 𝜈̅ values below the gas phase frequency of 2232 cm -1 , consistent with attractive electrostatic C≡N-charge interactions. In contrast, most H-bonding environments with water give rise to frequencies > 2232 cm -1 , indicative of the H-bonding blueshift.