Abstract: A method, system, and computer-readable medium for identifying and creating a database of isomers and isobars of molecules including the steps of performing isomer or isobar separation on molecules to obtain separate isomeric or isobaric molecules, measuring mass-to-charge ratios (m/z) to obtain IR fingerprints of the separate isomeric or isobaric molecules, and storing first data on the mass-to-charge ratios (m/z) and/or the IR fingerprints of the separate isomeric or isobaric molecules to a database.