The quantized difference between energy levels corresponding to different orientations of the nuclear spin Δ Δ E = γ γ ℏ ℏ B . The ratio of nuclei in the lower energy state, with spin aligned to the external magnetic field, is determined by the Boltzmann distribution. Thus, multiplying the dimensionless g -factor by the nuclear magneton and the applied magnetic field, and dividing by the product of the Boltzmann constant and the temperature.