We often classify the electrons in an atom as being either ‘core’ electrons—those closest to the nucleus— or ‘valence’ electrons, those involved in chemical bonding. Indeed, if the atom is part of a molecule, these electrons connect it to its neighbours. In this case, these valence electrons are delocalized over the entire molecule, making it difficult to identify which atom they really belong to. Now, a team of French, Swedish, and American scientists has managed to trace the origins of valence electrons that are ejected when x-rays strike a molecule. They were able to achieve this result thanks to the sensitivity and accuracy of the measuring instruments available at the PLEIADES beamline at the Synchrotron SOLEIL laboratory. Their work will appear in Nature Communications on 9th May, 2014.
