Halogen Bridges as Catalysts (IMAGE) Technical University of Munich (TUM) Caption Halogen bridges of two iodine atoms (blue) loosen the chlorine (green)-carbon (gray) bond, helping to replace the chlorine with another building block. Credit Stefan Huber / TUM Usage Restrictions None License Licensed 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.