Nuclear Magnetic Resonance Spectroscopy Nuclear spins are oriented randomly in the absence (a)of an external magnetic field but have a specific orientation in the presence(b)of an external field,Bo n Some nuclear spins are aligned parallel to the external field Lower energy orientation More likely Some nuclear spins are aligned antiparallel to the external field Higher energy orientation Less likely (a) (b) 0 Nuclear spins are oriented randomly in the absence (a) of an external magnetic field but have a specific orientation in the presence (b) of an external field, B0 ▪ Some nuclear spins are aligned parallel to the external field ▪ Lower energy orientation ▪ More likely ▪ Some nuclear spins are aligned antiparallel to the external field ▪ Higher energy orientation ▪ Less likely Nuclear Magnetic Resonance Spectroscopy