15 Lesson 4: Quantum numbers
To describe the energy of electrons in multi-electron atoms we need four quantum numbers:
1Principal
Symbol
- n
What it describes
- Distance of the electron from the nucleus (main energy level)
2Subsidiary (secondary, azimuthal)
Symbol
- ℓ
What it describes
- Shape of the electron cloud in the sublevel; the sublevels
3Magnetic
Symbol
- mℓ
What it describes
- Orientation of the orbital in space; number of orbitals
4Spin
Symbol
- ms
What it describes
- The spin motion of the electron about its own axis