# On what quantum level should g orbitals start to exist?

• $n$ is the principal quantum number, describing the energy level an electron is in. It is the coefficient in front of a given orbital. $n = 1 , 2 , 3 , . . .$
• $l$ is the angular momentum quantum number, describing the shape of the orbital. $l = 0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , . . . , n - 1$ describes $s , p , d , f , g , h , i , k , . . .$ orbitals.
$g$ orbitals have $l = 4$, but the maximum $l$ is $n - 1$. Therefore, $g$ orbitals can only exist starting at $\textcolor{b l u e}{\underline{\boldsymbol{n = 5}}}$. (Thus, there are no such things as $1 g - 4 g$ orbitals.)
And even then, as we generally regard $g$ orbitals as $\left(n - 3\right) g$, only atoms after Oganesson ($Z = 118$) (i.e. on the $8$th row and past) would even use $5 g$ orbitals. We're not there yet.