Aromatic ring currents are relevant to NMR spectroscopy, as they dramatically influence the chemical shifts of 1H nuclei in aromatic molecules. The effect helps distinguish these nuclear environments and is therefore of great use in molecular structure determination. In benzene, the ring protons experience deshielding because the induced magnetic field has the same direction outside the ring as the external field and their chemical shift is 7.3 ppm compared to 5.6 for the vinylic proton in cyclohexene. In contrast any proton inside the aromatic ring experiences shielding because both fields are in opposite direction. This effect can be observed in cyclooctadecanonaene (annulene) with 6 inner protons at −3 ppm.