Central Atom

[Michael Du 1E]

Why is it that in some problems or molecules, the central atom doesn't follow the lower ionization rule? Say for example, CH3Br, I would assume Br would be the central atom since Br has a lower ionization energy as it has a larger radius. However, C would be the central atom rather than Br. thank you.

[Rida Ismail 2E]

I just checked this and C does have the lowest IE.
Ionization energies:
C: 1086.5 KJ/mol
H:1312 KJ/mol
Br:1139.9 KJ/mol

Looking at this the IE of carbon is the lowest out of all of the atoms, therefore it goes in the center.

[Avnita C_4B]

most of the times, the central atom is always the one with the lowest ionization energy. In this case, even though Br sounds like a perfect match, if you look up the ionization energy of the elements, carbon is slightly lower than bromine.

[MMckinney_4H]

Given that we can't look up stuff during the midterm, what would be the best way of figuring out which one goes in the middle for this situation?