Originally Posted by
Win2Win
Because of its nuclear spin properties, this isotope responds to a resonant radio frequency (RF) signal. The absorption and emission of the RF signal by the nuclei can be monitored and detected using nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy. This is a technique that gives information on the identity and number of atoms adjacent to other atoms in said molecule, thereby giving clues to the structure of an organic molecule. Since 12C has zero spin, it does not give an NMR signal, and since only 1% of the atoms in a molecule are 13C, it is unlikely that carbon-carbon coupling is seen. Acquiring a 13C NMR spectrum can take from a couple of minutes to hours because many scans have to be summed together in order to have results distinguishable from background noise.