A novel microscope pins down the miracle of molecular oxygen Researchers at the University of Regensburg track the first step of the reaction of one single dye pigment with oxygen at unprecedented resolution.
An international research team directed by Prof. Jascha Repp has now succeeded in revealing how the triplet energy is transferred from one single dye molecule to one single oxygen molecule. The team now succeeded in tracking this transfer of energy between dye and oxygen molecule directly in space, without destroying the dye molecule. To do this, single molecules were placed on a surface and cooled to very low temperatures close to that of the universe. Using a so-called atomic force microscope consisting of a very fine needle with just one single atom at its tip, the researchers were able to image the individual atoms of the dye molecule by scanning the tip across it. By employing a clever sequence of electrical pulses applied to the dye molecule, it could be driven into the magnetic triplet state in a controlled fashion. The energy transfer from this excited triplet state to oxygen molecules nearby was then tracked in time by measuring miniscule changes in the force acting on the tip. This novel approach, reported in the leading journal Science, allowed the researchers to probe many different geometries of the arrangement of dye molecule and oxygen. See Jinbo Peng, Sophia Sokolov, Daniel Hernangómez-Pérez, Ferdinand Evers, Leo Gross, John M. Lupton, Jascha Repp, ?Atomically resolved single-molecule triplet quenching“, Science (2021) DOI: 10.1126/science.abh1155 https://dx.doi.org/10.1126/science.abh1155)