expanded octet

[josmit_1D]

Why do lewis structures with expanded octets have lower energy than octet structures?

[Adam Kramer 1A]

Lewis structures with expanded octets would have lower charges than octet structures because they are forming the structure that would provide the lowest possible energy, allowing the molecule to go to larger subshells to reach that lower energy level. They are going into the d-subshell which provides lower energy for the molecule with more space than a normal octet structure.