Exceptions outside the ones we memorized

[Simrah_Ahmed1J]

I know we had to memorize that H, He, Li, and Be as able to have less than an octet, and P, S, and Cl as able to have more than an octect of electrons, but there are also other atoms besides those that come up regularly that are exceptions as well. What are some of them/the most important ones?
just to make sure that if I do come across them when trying to come up with a molecule they will look more familiar and I won't be completely thrown off.

[SophiaBarden 2E]

Many atoms that have access to the d orbital can have expanded octets. In general, we probably wont see any outside of the normal ones like P, Si, Cl, S, but basically any element beyond the third principle level is able to form expanded octets!

[Khoa Vu 3l]

You should also remember some of the other atoms that form incomplete octets, like Boron, e.g. BF3, and Al, e.g. AlCl3. It would be good to remember these also because they are lewis acids and will accept an electron pair to complete their octet.

[AnjikaFriedman-Jha2D]

Boron is another atom that often has only 6 electrons and then will form a coordinate covalent bond with another atom supplying both electrons

[Yuehan_Wu_3K]

The excpetions are just p,s,cl who can accomdate more than 8 electrons.

[George Hernandez 3I]

Expanded octets are the norm, not the exception. Mostly any atom past the third row can utilize expanded octets to create unique bonding shapes.

[sabrina ghalambor 2J]

i'm fairly certain that any d-block element in groups 15,16,17, and 18 can have an expanded octet, but to different extents