Highly oxygenated organic molecules (IMAGE) Max Planck Institute for Chemistry Caption The figure shows that highly oxygenated organic molecules with high unsaturation (HU-HOMs) are formed by the multigenerational photo-oxidation of large polycyclic aromatic hydrocarbons (PAHs) on soot. Credit https://doi.org/10.1016/j.chempr.2022.06.011 Usage Restrictions The images may only be used in the context of scientific reporting about research at the Max Planck Institute for Chemistry. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.