Effects of Cross - Correlations in 2 D NOE Experiments 1

The development of two dimensional Fourier transform NMR techniques by Professor Ernst during the Seventies and Eighties created a revolution in the study of biomolecules by NMR. The ubiquitous COSY experiment and its many variants, especially the DQFC and TOCSY experiments made it possible to obtain assignments of resonances of molecules containing several hundreds of protons a task which was considered "impossible" before the development of 2D NMR. Similarly the impact of the 2D NOE experiment was "electrifying". It made it possible to obtain the structures of biomolecules in solution, a task which was considered "very difficult" before the application of this experiment (1-5). The revolutionary developments of Fourier transform NMR spectroscopy in one and multidimensions by Professor Ernst, with literally hundreds of new experiments developed by him during these two decades, leading to an explosion of research in this area by many workers, have culminated in his receiving the 1991 Nobel Prize in Chemistry.