NMR Spectroscopy
What is shielding in NMR?

Blocking parts of a molecule from Rf radiation
Using a curved piece of metal to block an opponents attack
When the magnetic moment of an atom blocks the full induced magnetic field from surrounding nuclei
Putting metal around an Rf source

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NMR Spectroscopy
Coupling causes the peaks in 1H NMR spectra to be split into

two peaks
multiple peaks equal to the number of hydrogen on surrounding atoms, plus one
multiple peaks equal to the number of surrounding carbon atoms
multiple peaks equal to the number of hydrogens on surrounding atoms

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NMR Spectroscopy
All hydrogen atoms

resonate at about the same frequency as carbon
have the same resonance frequency
are attached to carbon
resonate at different frequencies depending on their environment.

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NMR Spectroscopy
Why is it important to use a deuterated solvent?

So the spectrometer can lock onto the sample to prevent the spectrum from drifting during aquisition
NMR uses least of this solvent
They dissolve polymer the fastest
Expensive solvents work best with NMR

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