Since the chemical shifts δ of CO2 for parallel and perpendicular orientation are known (𝛿 || = -90 ppm and 𝛿 ⊥ = 245 ppm, using TMS as reference ) and the chemical surrounding is anisotropic in only one spatial dimension, the chemical shift δ can be expressed as a function of only the orientation of the CO2 molecule with respect to the external magnetic field 𝐵 0 ⃗⃗⃗⃗ .