Phase-corrected transmittance spectrum

Suppose that the transmitter is placed in the middle of the shift range and that a 90° pulse of width 20 /xs is used to excite the spectrum. Estimate the size of the phase correction which will be needed at the edges of the spectrum. (Assume that the spectrometer has a Bq field strength of 9.4 T). 

Zero-order phase correction is even easier to understand. It lines up the phase of the receiver with the phase of the transmitter so that a resonance that is exactly on resonance will appear purely absorptive—i.e., with no dispersive character. Zero-order phase correction affects every resonance in the entire frequency spectrum by the same amount. 

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