document: Nuclear magnetic resonance molecular photography A procedure is described for storing a two-dimensional -LRB- 2D -RRB- pattern consisting of 32 * 32 = 1024 bits in a spin state of a molecular system and then retrieving the stored information as a stack of nuclear magnetic resonance spectra . The system used is a nematic liquid crystal , the protons of which act as spin clusters with strong intramolecular interactions . The technique used is a programmable multifrequency irradiation with low amplitude . When it is applied to the liquid crystal , a large number of coherent long-lived / sup 1/H response signals can be excited , resulting in a spectrum showing many sharp peaks with controllable frequencies and amplitudes . The spectral resolution is enhanced by using a second weak pulse with a 90 degrees phase shift , so that the 1024 bits of information can be retrieved as a set of well-resolved pseudo-2D spectra reproducing the input pattern
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