November 26, 2024, 06:24:29 PM
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Topic: how much the signal strength difference between Deuterium and hydrogen In HNMR?  (Read 5370 times)

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Offline diccup

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Is there any data for signal strength between Deuterium and hydrogen In HNMR?

If I have 99% Deuterated CDCL3, then I can say 1% of CHCL3.
Usually, Peak of Deuterium is a lot smaller than that of Hydrogen,
I am thinking hydrogen peak can screen Deuterium peak? In other words, Deuterium peak is not showing because of hydrogen peak. Is it possible?

In HNMR, Peak showing from 99% CDCL3 is from CDCL3 or CHCL3?

Thanks,


Offline James Newby

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Im not sure how much H NMR you have done but Deuterium isnt spin active so you dont see a peak.  Hence the use of deuterated solvents! Usually the CDCl3 can swap its Deuterium for a labile H so a small peak is observed around 7ppm.
4th year undergraduate at the University of Sheffield

Offline Squirmy

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The Deuterium nucleus has spin (I)= +1, so you can actually run a deuterium NMR. In fact, the deuterium signal from the solvent is frequently used to "lock" the sample to account for drift of the magnetic field and to shim the magnet to give a more homogeneous magnetic field.

Deuterium nuclei just resonate at a different frequency, so you don't see them in a proton NMR. The small peak is residual CHCl3, which is there from the percentage of deuteration. There may also be D-H exchange, but that peak will be there without it.   

Offline diccup

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Thank you so much.

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