Process for the excitation and acquistion of nuclear magnetic resonance signals, particularly in light water

Process for the excitation and acquisition of high resolution NMR signals, for the analysis of molecules dispersed in a solvent, comprising the steps of:

• subjecting a specimen to be analyzed to a series of impulses (1) corresponding to a high resolution NMR test to be carried out,
• applying to the specimen a first pulsed field gradient (2) in a given direction,
• subjecting the specimen to a 180.degree. selective pulsed radiofrequency field (3) affecting all the spectrum except the resonance frequency of the solvent, an excitation profile of said 180.degree. selective pulsed radiofrequency field (3) varying in intensity by less than 10% in an excited spectrum;
• and
• applying to the specimen a second pulsed field gradient (4) identical to the first and then effecting the acquisition and processing of the resulting NMR signals.