General principles and homonuclear correlation experiments

Using this pulse sequence a series of experiments is performed in which the delay t between two 90° pulses is varied. The first 90° pulse creates magnetization in the transverse plane. During the evolution time (tj) 

NMR spectra of the palladium complex whose structure is displayed, showing the resonances of (a) CH3 groups, (b) CH2 groups, (c) CH groups and (d) quartemary carbon atoms only. Spectra (a), (b) and (c) were obtained using variants of the DEPT pulse sequence, followed by Unear combination of the three original DEPT spectra. 

There is a large variety of 2D NMR experiments, some homonuclear, such as the COSY experiment described above, and some heteronuclear, giving correlations between different nuclei. What the two frequencies (related to 2 and fi) represent depends on the type of 2D spectrum. They can be chemical shifts or 

An alternative solution to the problem of the low abundance of neighboring pairs is to use 2D 

INADEQUATE spectra (Incredible Natural Abundance Double Quantum Transfer Experiment). However, this experiment is rarely used, and then most often to detect couplings in organic molecules, in order to estab- 

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