Data Accessibility: The MultiXC-QM9 data set is available on Figshare platform at and provides information on both molecules and reactions in separate files. Energy calculations for molecules are provided in CSV and SQLite formats. CSV format contains energies from various DFT and semi-empirical methods, SMILES strings derived from xyz files, and chemical formulas for each molecule. The SQLite format stores xyz coordinates, energies, and other relevant properties derived automatically by atomistic simulation environment. Reaction data is provided in CSV format which includes reaction energies, indices of reactants and products, and SMILES strings for both reactants and products.