Mol2Raman: a graph neural network model for predicting Raman spectra from SMILES representations

Raman spectroscopy is a powerful technique for probing molecular vibrations, yet the computational prediction of Raman spectra remains challenging due to the high cost of quantum chemical methods and the complexity of structure-spectrum relationships. Here, we introduce Mol2Raman, a deep-learning framework that predicts spontaneous Raman spectra directly from SMILES representations of molecules. The model leverages Graph Isomorphism Networks with edge features (GINE) to encode molecular topology and bond characteristics, enabling accurate prediction of both peak positions and intensities across diverse chemical structures. Trained on a novel dataset of over 31 000 molecules with state-of-the-art Density Functional Theory (DFT)-calculated Raman spectra, Mol2Raman outperforms both fingerprint-based similarity models and Chemprop-based neural networks. It achieves a high fidelity in reproducing spectral features, including for molecules with low structural similarity to the training set and for enantiomeric inversion. The model offers fast inference times (22 ms per molecule), making it suitable for high-throughput molecular screening. We further deploy Mol2Raman as an open-access web application, enabling real-time predictions without specialized hardware. This work establishes a scalable, accurate, and interpretable platform for Raman spectral prediction, opening new opportunities in molecular design, materials discovery, and spectroscopic diagnostics.