MODEL RELEASED: NMR spectrometry. Screen display of a Nuclear Magnetic Resonance spectrometer. In the background, a scientist is seen loading a sample into the NMR spectrometer's magnet. This device measures the resonance between an applied oscillating magnetic field and the magnetic moment of atoms. The display seen here is a '2D' trace. This is a plot of excitation frequency on one axis, resonance frequency on the second axis and response intensity in the vertical axis. This type of plot is used to identify the consituents of a compound and to give some data relating to its structure.