Electronegativities of the noble gases can be calculated more easily from ioniza tion energies than from bond energies. Because the noble gases have higher ionization energies than the halogens, other calculations have suggested that the electronegativi ties of the noble gases may match or even exceed those of the halogens (Table 3-3) The noble gas atoms are somewhat smaller than the neighboring halogen atoms (for ex ample, Ne is smaller than F) as a consequence of a greater effective nuclear charge. This charge, which is able to attract noble gas electrons strongly toward the nucleus, is also likely to exert a strong attraction on electrons of neighboring atoms; hence, the high electronegativities predicted for the noble gases are reasonable.