Table of Contents

1. Summary
2. Step 1: Inspect the FID
3. Apodization

Summary

When you have a suite of NMR data,

Make sure to get the chemical shifts right from the get go.

Step 1: Inspect the FID

Let’s remember what an FID is. Lots of signal at the beginning, not much at the end (where it is mostly noise).

If there are beats, double check shimming.

Multiply FID by some function.

Apodization

Since the end of the FID is mostly noise, you can apply an exponential curve to the data to increase the signal at the beginning and decrease it at the end.

Applying an exponential increases signal to noise, but it also broadens the peaks. This is not so much a problem for a carbon spectrum.

You can combine an exponential of -0.1 Hz with a Gaussian of 1 Hz to enhance the middle of the FID. This screws up integration, but you can get better peak resolution.