1 NMR Data Processing FT Free Induction Decay (FID) Time DomainFrequency Domain Intensity decreases with time. Why?

2 1. Solvent suppression 2. Window function 3. Zero filling 4. Fourier Transformation 5. Phasing X=detection dimension

3 Can only  resolution at the expense of S/N or vice versa Enhance S/N -by weighting earlier part of FID

4 Or Exponential Multiplication (EM): enhance S/N with lb

5 Zero Filling or Linear Prediction both extend np i.e. enhance resolution

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7 Phase correction: Phase errors arise because detection of an NMR signal (FID) can begin at any point in an oscillation, depending on the instrumental and experimental parameters. They appear as twists in the baseline of the Fourier-transformed spectrum, and are corrected automatically by the spectrometer's computer or manually by trial-and-error. Phase correction

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9 Y=second or first indirect dimension