The sample will be affected by the magnetic field as long as it contains either protons, neutrons ... usually extract the following information from NMR spectra: Chemical shift values, coupling ...

(This is the direct through-space interaction between pairs of magnetic dipoles, not the J-coupling seen ... is unusual to achieve proton line widths less than about 0.5-1 ppm, rather unsatisfactory ...

Nuclear Magnetic Resonance (NMR) was first experimentally observed in late 1945, nearly simultaneously by the research groups of Felix Bloch, at Stanford University and Edward Purcell at Harvard ...