Graphormer-IR performed best on liquid film spectra (𝑆𝐼𝑆 𝜇 = 0.8868, see figure ), which is likely because it is the phase that is least likely to exhibit complex phase absorbance, because liquid samples are simply measured between NaCl plates that don't interact with IR radiation. Spectra measured in nujol mull (𝑆𝐼𝑆 𝜇 = 0.8437) and KBr disks (𝑆𝐼𝑆 𝜇 = 0.8338) had intermediate absorbances likely due to inconsistencies that were not eliminated by baseline correciton. Spectra in nujol mull often exhibited solvent absorbance outside of the excluded range discussed above, and KBr disk spectra often had broad regions of absorbance from moisture. Spectra measured in CCl4 had the lowest average 𝑆𝐼𝑆 𝜇 of 0.8138 due to their relative underrepresentation in the dataset (see Figure ). Figure also demonstrates the intended effect of the baseline corrections. Gas-phase spectra best represent the fundamental interactions (without noise or solvent interference) that are sought from IR spectra. In an ideal world, the performance of the solvent-phase IR spectra after inclusion of the global node would on average roughly correspond to the gas-phase spectra because it best represents the prediction task. The solvent doesn't fundamentally change the underlying chemistry of an IR spectrum (assuming that solvent peaks are excluded) and the "goal" of predicting vibrational peaks is best represented by the successful prediction of gas phase IR spectra. The phase and its associated baseline should introduce local variance (positive or negative) to the ensemble of test scores. In the case of the original Chemprop-IR dataset where no baseline correction was applied, this variance was purely positive, resulting in SIS scores where the gas phase predictions perform poorest and 𝑆𝐼𝑆 𝐶𝐶𝑙 4 > 𝑆𝐼𝑆 𝐿𝑖𝑞𝑢𝑖𝑑𝐹𝑖𝑙𝑚 > 𝑆𝐼𝑆 𝑁𝑢𝑗𝑜𝑙 > 𝑆𝐼𝑆 𝐾𝐵𝑟 > 𝑆𝐼𝑆 𝐺𝑎𝑠 . Given that more baseline-heavy phases have higher average performance, it is likely that the model is learning the solvent baseline introduces systematic positive bias and deviates from the goal of predicting vibrational frequencies. The Graphormer-IR predictions on the baseline-corrected dataset do not exhibit this systematic bias (See figure ), where 𝑆𝐼𝑆 𝐿𝑖𝑞𝑢𝑖𝑑𝐹𝑖𝑙𝑚 > 𝑆𝐼𝑆 𝐺𝑎𝑠 > 𝑆𝐼𝑆 𝑁𝑢𝑗𝑜𝑙 > 𝑆𝐼𝑆 𝐾𝐵𝑟 > 𝑆𝐼𝑆 𝐶𝐶𝑙 4 The gas phase performance is near the center of the phase distribution and most closely resembles the overall average (𝑆𝐼𝑆 𝑔𝑎𝑠 = 0.8567, 𝑆𝐼𝑆 𝜇 = 0.8531), which was not true for Chemprop-IR predictions (𝑆𝐼𝑆 𝑔𝑎𝑠 = 0.837, 𝑆𝐼𝑆 𝜇 = 0.864). As such, we posit that training on the baseline-corrected dataset provides a much better measure representation of the prediction of the vibrational frequencies without prediction of the solvent noise.