Included well-resolved, high-quality spectra to limit the effects of noise on learning. To these ends, only molecules containing main block elements (H, C, N, O, F, Si, S, P, Cl, Br, I) were considered. An analysis of the representation of these elements and the distribution of molecular weights is available in figure . Any species containing adducts, dimers, multimers or ionic complexes (i.e., salts) were excluded from the dataset. Low quality spectra (i.e., broad peaks, noisy spectra, contamination from water at 3,400 cm -1 ) were excluded from the dataset at the discretion of the authors. After pruning, the final dataset contained 53,528 spectra representing a total of 30,951 unique Simplified Molecular-Input Line-Entry System (SMILES) strings. While there is likely large overlap between our dataset and that produced by McGill, there are meaningful differences due to time between data collection and the stringency of data pruning. As such results obtained using our dataset and reported in reference 37 must be considered in isolation from one another. To account for this, we reproduce McGill's MPNN models and test performance on our dataset to provide a real comparison, which is discussed in more detail below.