Nuclear Magnetic Resonance. This tag relates to NMR spectroscopy, the experimental technique of measuring the resonance and thus deducing the molecular structure of the given compound.
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What is the multiplicity of this signal in the 1H NMR of glutamine in D2O
The 2 Hydrogens near the carbonyl (the lower 2 $\ce{H}$s are not bonded to the nitrogen) should be the most deshielded so I think they appear as the rightmost peak in the NMR. Are these 2 $\ce{H}$s a ...
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1H-NMR problem. Why are these hydrogen equivalent?
Above is a $^1H$ Nuclear Magnetic Resonance (NMR) spectrum for benzyl alcohol. The hydrogen in the alcohol group gives rise to a unique signal. The two hydrogens in CH2 give rise to a unique signal ...
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Can ammonia be detected by a 1D-1H-NOESY experiment?
I'm not detecting ammonia in my samples while using a NOESY pulse program for a 1H-NMR experiment.
Is it possible for ammonia to be detected by a 1D-1H-NOESY experiment?
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What is deuterium-depleted water actually used for?
I noted, flipping through the paperback Alfa Aesar catalogue today, that they sell deuterium-depleted water. Under the usage category, they list 'NMR'. I'm trying to work out what specific use this ...
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Why is the Gaussian Window Function used to enhance resolution in 1D NMR spectra?
In a recent question it was explained that Gaussian window functions are not used in 2D NMR spectra as they can introduce artifacts into the spectrum baseline by truncating the FID. Why then are they ...
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Why is a squared cosine window function commonly used for 2D spectra?
In nearly all default parameter sets for 2D NMR experiments on Bruker spectrometers, the window function is set to a pure squared cosine function for both dimensions (...
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Why do aromatic hydrogen atoms have a higher chemical shift value compared to aliphatic hydrogen atoms?
In Nuclear magnetic resonance (H-NMR) spectroscopy, the chemical shift of aliphatic hydrogen atoms are very much closer to the 1.0 ppm than that of aromatic hydrogen atoms.
Aromatic hydrogen atoms ...
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Can a NOESY NMR experiment be halted partway through and give meaningful results?
Some NMR experiments can be halted partway through the acquisition and still give perfectly valid results: The traditional 1H experiment for example. Others, like a Saturation Transfer Difference ...
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Why is it so difficult to create mock NMR spectra of macromolecules?
From what I understand, if you have a NMR spectra, you can determine the structure of a macromolecule but it is very difficult to determine what the NMR spectra of an expected structure would look ...
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13C NMR spectrum only showing solvent
This is my first time taking a 13c NMR spectrum and while I'm aware the signal to noise ratio is much lower compared to 1H NMR, I didn't realize it was quite this bad. I took a spectrum and I only see ...
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Regenerating the imaginary data of a 2D NMR spectrum with a hilbert transform
2D spectrum take up a large amount of hard disk space. At my last lab it was standard practice to delete the imaginary portions of the spectrum with xfb n (We used ...
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What is the difference between an HMQC and HSQC experiment?
This afternoon, I was having some trouble with an HSQC (Heteronuclear Single Quantum Coherence Spectroscopy) spectrum I was trying to aquire, and the spectroscopist recommended I try an HMQC ...
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What factors are important for quantitative analysis of a proton 1D-NMR spectrum?
Besides elucidating or verifying a chemical structure, NMR can also be used e.g. for quantifying a mixture of different chemicals.
Depending on the quality of the spectrum and the specific ...
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What benefits do higher-rated NMR tubes provide?
You can buy NMR tubes in a huge variety of qualities, with an equally huge difference in price between the cheapest and the most expensive NMR tubes. They are usually rated for a specific spectrometer ...
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Splitting of multiplets in ¹H NMR spectra?
I'm currently taking VCE (Victorian Certificate of Education) Chemistry classes, and we're currently studying the interpretation of spectra produced by Hydrogen NMR (Nuclear Magnetic Resonance) ...
