Chargephilicity and chargephobicity: Two new reactivity indicators for external potential changes from density functional reactivity theory

In analogy to the electrophilicity and the potentialphilicity, we define the chargephilicity and chargephobicity to describe the energetic response of a molecule to a change in its charge distribution. The chargephilicity captures the ‘best’ way to change the underlying charge distribution; the chargephobicity captures the ‘worst’ way to change the underlying charge distribution. The Coulomb potential induced by the linear-response function plays a very important role in this approach, analogous to the role of the hardness for the electrophilicity, the hardness kernel for the Fukui function, and the linear-response function for the potentialphilicity and potentialphobicity.