NMR Blog

The total echo experiment (which refocuses both J-coupling and Chemical Shift interactions at the same time) allows the user to collect the zero time echo point which otherwise is impossible in a normal Hahn Echo/CPMG/PIETA experiment. When the user wishes to collect a whole echo with each refocus period, you need the TE-PIETA approach (or a comparable total echo approach). The four-dimensional data is reduced by removing the 2 phase dimensions down to a two-dimensional dataset. An example of this reduced data is given in the following PDF file. Once the 2D FT is applied, we arrive at a dataset that correlates the isotropic chemical shift in the horizontal dimension with the J-coupling in the vertical dimension of this PDF. Slices through the two types of sites (Q0 and Q1) are shown in this PDF.