The electron density surrounding carbon atoms in organic molecules predicts a compound’s stability. Chemists instinctively know that “too many” electron-withdrawing groups means they have a reactive or unstable compound. But electron density is difficult to quantify so Andrej Krzan and Janez Mavri, National Institute of Chemistry, Slovenia, have turned to the Atoms in Molecules (AIM) quantum theory. They use this to calculate atomic charges and volumes of carbon atoms in molecules with lots of oxygen atoms.

These two parameters offer quantitative descriptors of electron depletion and so can be used to predict whether a novel compound might be highly reactive or wholly unstable.

• Atomic Volume as a Descriptor for Carbon Electronic Structure and Stability,
  A. Krzan, J. Mavri,
  J. Org. Chem. 2011.
  DOI: 10.1021/jo102152s