Li and F, the former pair undergo a more drastic change upon bond formation, eventually differing by 44.4 eV×e -1 (Table ). With our perspective, GaN is composed of highly electronegative Ga, while bound N takes an electronegativity comparable to atomic Cs. We primarily attribute the larger magnitude of the electronegativity inversion to a larger number of formally exchanged electrons (three), compared with in LiF (one). At the same time, we emphasize that the utility of in-situ electronegativities go well beyond a secondary description of charge transfer. It provides spatial information of electron binding. Our data in Table predicts that electron detachment from GaN should occur from primarily N valence electrons.