If you know that a spectrum is phase-sensitive or "echo-antiecho", use the corresponding shuffling along the indirect dimension, but never along the direct one. When you have found the right phase parameters, you can add zero-filling or LP-filling. If you have troubles with the phase correction, use a sine bell shifted by 90 degrees along f2 and a squared sine bell shifted by 90 degrees along f1, and do not use neither LP-filling nor zero-filling. The only exception I remember is represented by Bruker spectra in pure "TPPI" mode, which require "Real FT" only along f1. The only exception I remember is represented by Bruker spectra in "States-TPPI" mode, which require "swap sides" only along f2. In such case, ignore outlier peaks and phase the rest. When the pulse sequence become longer, and if you add a pre-saturation step, phasing all peaks may become impossible. With the classic NOESY, TOCSY and ROESY experiments it is possible to bring in phase all signal simultaneously. If you get the correct number of peaks in the correct chemical shift order, your parameters are correct. If your FT parameters are wrong, you get all the signals doubled, or they fall at the wrong chemical shift, or both things happen. First thing first: you should determine if yours is a problem of phase or a poor choice of FT parameters. Demonstration of the corollary is left to the reader as an exercise. Being this in contrast with the definition, the theorem is demonstrated. The dimension with the highest index is called "direct", all others being "indirect".īruker calls "f2" the indirect dimension and "f1" the direct one. It is necessary, therefore, to learn some theory. Processing a 2D spectrum can sometime become a puzzle.
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