Why does the Lewis structure of XeF4 not follow the octet rule?
The octet rule states that atoms want to fill their outer valence shell with 8 electrons, this molecule defies this rule because in seeking a formal charge of 0,
The Lewis Structure for this molecule is:
The octet rule states that atoms seek to surrounded by 8 electrons each to fill their valence shells. This rule is not law, and has various exceptions regarding transition metals, but for noble gases and group period 1-3 elements, it's fairly reliable.
So, applying this rule to the above structure, we see that
Its formal charge is 0, but it has 12 electrons surrounded about it. Hence, it doesn't follow the octet rule.