The Ullmann reaction examined is a chemical reaction in which silver atoms catalyze the bond between two carbon atoms to which iodine was previously bonded. Although scientists have known about this type of reaction since 1901 and used it for many important chemical conversions, it was not previously possible to observe the intermediate product of the reaction in detail. Physicists at the University of Basel have succeeded in watching a silver catalyst at work for the first time with the aid of an atomic force microscope. The observations made during an Ullmann reaction have allowed the researchers to calculate the energy turnover and, potentially, to optimize the catalysis. Surprisingly, it was revealed that the silver atoms react with the molecules at temperatures of around -120 °C and seem to curve like a bridge over a river. In the second stage of the reaction, which requires the temperature to be increased to around 105 °C and generates the end product, the silver atoms are freed again and two carbon atoms bond together. https://www.unibas.ch/en/News-Events/News/Uni-Research/Researchers-Watch-Catalysts-at-Work.html
