Proton Nuclear Magnetic Resonance (NMR) is an analytical technique that exploits the spin of odd-mass-number nuclei (here, hydrogen protons), which align with or against an external magnetic field and absorb radio-frequency energy at a resonant frequency to flip spin states, producing a spectrum of chemical shift (ppm) versus signal. Three properties of the resulting peaks carry structural information: chemical shift (position, governed by shielding/deshielding from nearby electronegative atoms), integral (peak area, proportional to the number of equivalent protons), and multiplicity or splitting (governed by spin-spin coupling with protons on adjacent carbons, predicted by the n+1 rule). This belongs to organic chemistry's structural elucidation methods, alongside other spectroscopic techniques such as IR and mass spectrometry, and provides a way to infer molecular structure from the magnetic environment of hydrogen atoms.
Proton Nuclear Magnetic Resonance (NMR) is an analytical technique that exploits the spin of odd-mass-number nuclei (here, hydrogen protons), which align with or against an external magnetic field an…