Antiecho mode

We also have to think about the phase sensitive detection in both indirect dimensions. For example, if the phase is encoded in States mode in t and in echo-antiecho mode (using gradients) in t2, we have to acquire four FIDs for each combination of t and t2 delay values. States mode real or imaginary is selected by using an x or y phase for the pulse just before the t delay (lH SQC), and echo or antiecho mode is selected by using a negative gradient... 

In the following discussion the experimental procedures to extract frequency discriminated spectra with pure absorptive lines from amplitude modulated data is outlined. The analogous procedure for phase modulated data is discussed in the paragraph on the Echo/Antiecho detection mode. As shown in equation [2-15] taking the... 

Combination of gradients amplitudes and stored signal functions in the Echo/Antiecho detection mode. 

The quadrature detection mode is given as a suffix to the main sequence name me magnitude calculated, TPPI time proportional phase increment, E/A Echo / Antiecho The term "selective" is reserved exclusively for sequences using selective pulses. If selectivity is achieved using other methods this is defined using a different term. 

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