Chemists use a wide array of techniques for determining the exact composition and structure of a compound. One of the most robust and interesting of these is nuclear magnetic resonance (NMR) spectroscopy. In this problem, you will see how NMR spectroscopy allows for the precise determination of the structure of an organic compound. Nuclei with odd numbers of neutrons or protons have a magnetic moment. In the presence of a strong magnetic field, some nuclei will align parallel and some will align antiparallel to the field. If a sample is subjected to electromagnetic radiation with photon energy equal to the difference in energy between the two nuclear alignment states, some nuclei in parallel states will absorb a photon and flip to antiparallel states.