For a hydrogen atom, an electron occupying the atomic orbital Ψ n,ℓ,m , the magnetic dipole moment is given by μ μ L = − − g L μ μ B ℏ ℏ ⟨ ⟨ Ψ Ψ n , ℓ ℓ , m | L | Ψ Ψ n , ℓ ℓ , m ⟩ ⟩ = − − μ μ B ℓ ℓ ( ℓ ℓ + 1 ) .