Can two electrons of paired spins be in the same orbital?
1 Answer
Aug 10, 2015
If by paired spins you mean opposite spins on the same pair of electrons in the same orbital, then yes, that must be the case.
Electrons are in a particularly special class of particles called fermions, which are antisymmetric with respect to interchange. That means that two identical electrons in the same orbital cannot physically exist if they both have the same spin, or if the orbital is claimed to somehow contain more than two electrons. Furthermore, if they are opposite spins, exchanging them means the orbital phases switch.
This is stated in the Pauli Exclusion Principle.
https://en.wikipedia.org/wiki/Pauli_exclusion_principle#Stability_of_matter
