How are electronic configurations including hybrid orbitals notated?

Question

I know the general scheme for notating electronic configurations is (with s and p orbitals) [noble gas core]ns^el.$n$p^el. etc., where $n$ is the principal quantum number and el. is the number of electrons occupying that subshell, e.g. carbon: [He]2s²2p².

Now, how do you include hybrid orbitals? The problem arises because some hybrid orbitals already have superscript numbers (sp², sp³ …) – how do you differentiate between these superscript numbers and those denoting how many electrons fill that orbital? If I were to write out the electronic configuration for the hybridised carbon atom in $\ce{CO2}$, this would not be a problem: [He]2sp²2p², but what about the carbon atom in $\ce{CH4}$, which has sp³ orbitals? Would you write [He]2sp^{3, 4} or [He]2sp₃⁴ or something else?

Answer 1

The electronic configuration concept does not really extend itself well to hybrid orbitals, because these are best considered mathematical concepts only. However, the problem is easily solveable:

Always use brackets when dealing with hybrid orbitals.

Even your $\ce{CO2}$ case is potentially misleading: I misread it once as $\mathrm{2s^1\ 2p^2}$. It is best to show what belongs together with: $\mathrm{[He]\ 2(sp)^2\ 2p^2}$ or, for methane: $\mathrm{[He]\ 2(sp^3)^4}$.