γ K are the i th and j th components of the electronic magnetic moment and hyperfine operators, respectively. The biderivative ∂ 2 Ĥ ∂ B i ∂ µ K j = Di j includes the diamagnetic orbital shielding contributions. Finally inserting the quantum mechanical expressions of energy coefficients in eq. 6 ultimately results in the sum-over-states formulation of the chemical shielding tensor according to eq. 8