Electron Density
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3D Electron Density Simulation
Four quantum numbers uniquely define the state of every electron in an atom
Determines the energy level (shell) and the size of the orbital. Larger n → higher energy, larger orbital, electron farther from nucleus.
Determines the shape of the orbital (subshell) and the angular momentum magnitude of the electron.
Determines the spatial orientation of the orbital. In a magnetic field, orbitals with different mℓ have different energies — the Zeeman effect.
Describes the intrinsic angular momentum (spin) of the electron. Electrons behave like tiny bar magnets. Two electrons sharing an orbital must have opposite spins.
| n | ℓ | Subshell | mℓ values | Orbitals | Max e⁻ | Shell Max |
|---|---|---|---|---|---|---|
| 1 | 0 | 1s | 0 | 1 | 2 | 2 |
| 2 | 0 | 2s | 0 | 1 | 2 | 8 |
| 1 | 2p | −1, 0, +1 | 3 | 6 | ||
| 3 | 0 | 3s | 0 | 1 | 2 | 18 |
| 1 | 3p | −1, 0, +1 | 3 | 6 | ||
| 2 | 3d | −2, −1, 0, +1, +2 | 5 | 10 | ||
| 4 | 0 | 4s | 0 | 1 | 2 | 32 |
| 1 | 4p | −1, 0, +1 | 3 | 6 | ||
| 2 | 4d | −2..+2 | 5 | 10 | ||
| 3 | 4f | −3..+3 | 7 | 14 |
Click any orbital card to jump to it in the 3D simulator