Chapter 2: Top Resolution in 2D NMR Spectroscopy Using Spectral Aliasing

Obtaining the maximal possible resolution in the indirect dimension of 2D NMR spectra may require a number of free induction decays that is too large to be applicable. When the sensitivity is not a limiting factor, linearly sampling a fraction of the full set of FIDs produces Fourier-transformed spectra without compromising resolution. The price to pay for the reduction of the total acquisition time is the introduction of ambiguities with respect to the scale of the indirect dimension called spectral aliasing or folding. These ambiguities can be resolved by complementary information originating from a reference low-resolution spectrum recorded with the same pulse sequence or other spectral sources such as a 1D spectrum. The linearity of aliased spectra makes them particularly suitable for the acquisition of any series of experiments following changes in a sample composition as a function of time, spatial dimensions, temperature and other physical or chemical transformations.