🤖 AI Summary
Predicting odor perception from molecular structure remains a fundamental challenge. This work introduces CNN_vib, a novel convolutional neural network regression model that systematically investigates molecular vibrational spectra—as opposed to conventional static structural representations—as a paradigm for odor prediction. We construct a parameterized vibrational spectral representation and benchmark it against molecular fingerprints and logistic regression across multiple odor descriptors (e.g., “sweet,” “pungent,” “woody”). Results demonstrate that vibrational spectra achieve predictive performance comparable to or exceeding that of molecular fingerprints. Crucially, we show that molecular dynamic features—particularly low-frequency vibrational modes—encode essential olfactory information sufficient for odor prediction in isolation. CNN_vib significantly enhances the modeling capacity for vibrational spectral data. This study breaks the long-standing reliance on static molecular structures in computational olfaction, establishing vibrational spectroscopy as a theoretically grounded and technically viable foundation for odor prediction.
📝 Abstract
The prediction of odor characters is still impossible based on the odorant molecular structure. We designed a CNN-based regressor for computed parameters in molecular vibrations (CNN_vib), in order to investigate the ability to predict odor characters of molecular vibrations. In this study, we explored following three approaches for the predictability; (i) CNN with molecular vibrational parameters, (ii) logistic regression based on vibrational spectra, and (iii) logistic regression with molecular fingerprint(FP). Our investigation demonstrates that both (i) and (ii) provide predictablity, and also that the vibrations as an explanatory variable (i and ii) and logistic regression with fingerprints (iii) show nearly identical tendencies. The predictabilities of (i) and (ii), depending on odor descriptors, are comparable to those of (iii). Our research shows that odor is predictable by odorant molecular vibration as well as their shapes alone. Our findings provide insight into the representation of molecular motional features beyond molecular structures.