| NMR Pulse |
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| A
radiofrequency pulse is a combination of a wave (cosine) of |
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| frequency wo and a step function |
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| * |
| = |
| tp |
| Pulse length (time, tp) |
| The fourier transform
indicates the pulse covers a range of frequencies |
| FT |
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| Hisenberg
Uncertainty principal again: Du.Dt ~ 1/2p |
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| Shorter pulse length –
larger frequency envelope |
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| Longer pulse
length – selective/smaller frequency envelope |
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| Sweep Width |
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| f ~ 1/t |
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