Talk:NMR spectroscopy/Draft

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 Definition The use of electromagnetic radiation, in the presence of a magnetic field, to obtain information regarding transitions between different nuclear spin states of the nuclei present in the sample of interest. [d] [e]
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 Workgroup categories Chemistry, Physics and Biology [Categories OK]
 Talk Archive 1  English language variant American English



Does the formatting look fine? As you can see by clicking the history tab, and the compare button, one needs to put titles between "==" to have them appear in the Table of contents. If you wish to make subsections, just use "===" and even "====". However, Citizendium disapproves excessively "modular" articles (with many subsections), and prefers lively narratives, but I can see that you are certainly not going in that direction (the excessively modular approach)! If I can help in any way (I'm just an author, however), please let me know by clicking my user name and then the "discussion" tab, where you can "edit" at the bottom of the page.

I removed your signature from the article, because those who wish to know who has been working on a given page normally click on the "history" button. I will now create redirect pages, which will enable users to access this page using the different abbreviations and alternate names you provide.

Pierre-Alain Gouanvic 11:56, 12 January 2008 (CST)

Some formatting pointers

Dear dr. Talluri, welcome again. I hope that you will contribute more articles of the same quality. I understand that you don't have any wiki experience yet. Therefore I mention a few things:

The wiki software knows LaTeX enclosed between <math> ... </math> An indented new paragraph is started by a colon (:),

like this. Hence indented math uses   :<math> ... </math>

As in printed text (in journals etc.) emphasis is done by italics, not by capitals (and also not by underlining). Wikilinks are done as [[NMR spectroscopy]] and give NMR spectroscopy.

If you don't want to be bothered by these finicky details, don't worry, others (including myself) will fix it. It is more important that you share your knowledge and expertise with us than that the format is perfect. --Paul Wormer 03:32, 13 January 2008 (CST)

I didn't nominate for approval, but it says i did

I have no idea why the article says I nonimated it for approval. I have not even read it through yet. Any help appreciated removing the approval. David E. Volk 16:38, 16 January 2008 (CST)

Editors, this article is set for approval tomorrow. As it is using the group editor approval method, it requires three editors to be on the template. David appears to be suggesting that he has not recommended it for approval(it's a year old?). Unless I hear otherwise, the comment above means I cannot perform the approval. D. Matt Innis 02:06, 17 January 2009 (UTC)

Way to go.

I see that the article is developing nicely, keep up the good work.--Paul Wormer 11:03, 19 January 2008 (CST)

The lede

This is turning into a really great article. We do need to improve the lede however to interest the casual reader. I have been refraining from working on the article so I could approve it later, but I forgot and wrote a liitle today, now we will need three editors for approval when ready. If we can spiff the rough edges, we can nominate for article of the week David E. Volk 14:09, 15 October 2008 (UTC)

Approval potential

Hello editors, I see three editors on the ToApprove template above, but am not convinced that all three are ready to approve the version chosen. Please leave a message here so that when I return tomorrow, I can be sure that all three are endorsing the version number that you choose (please make that clear as well by updating the version number in the template). Thanks, D. Matt Innis 02:12, 17 January 2009 (UTC)/constable

My name was incorrectly added to the Metadata template, without my knowledge, as an Approval nominator. Although I am a Chemistry Editor and a Physics Editor, I don't know enough about NMR to review or to approve this article. My name should be removed. Milton Beychok 02:56, 17 January 2009 (UTC)
I will start reading it tomorrow (January 18) and need, say, a week. I can approve it by myself, but I believe that David Volk and Daniel Mietchen are much better qualified. When they have time that would be nice. In any case I will put my name down and January 25 as approval date. If Daniel and David need more time they can move the date forward (or is it backward? I never know, I mean later). --Paul Wormer 16:22, 17 January 2009 (UTC)

minor changes please

This is looking great. First, minor edits needed:

  1. Section 2.1 uncapitalize tetramethylsilane since it is mid-sentence
  2. Section 2.2 repeat of "results results" should be edited
  3. For the FID diagram, fix the figure legend
  4. In the Biomedical section, remove cap letter on Sequential; it is mid-sentence

As for the layout: I would like to see a 1D and 2D spectrum near the top to give the new reader an idea of what they look like right at the start. I would also like to see an example of metabonomics (metabolomics) NMR taken from the literature, but that can wait for the next version.

Since I have refrained from working on this article (I think that is true), I can approve it single-handedly once the minor corrections are made by the principle author or Dr. Wormer. I have many images which I could upload and someone else can insert into the article. David E. Volk 16:36, 17 January 2009 (UTC)

my minor edits

It appears I accidently made very minor edits previously. Perhaps the constables can forgive such minor edits and still let me approve it. David E. Volk 16:39, 17 January 2009 (UTC)

Hi David, you are allowed to make copy edits to the text and still use the single editor approval, so you can make those that you have listed above - as long as you don't make any content changes. You can suggest content changes here on the talk page and others can make them for you. The edits that I saw from previously no longer exist as they have been integrated into the new version, so I don't see any problem with continuing with a single editor approval at this point, if that is what you are willing to do. D. Matt Innis 16:49, 17 January 2009 (UTC)

A brief review

  • I am glad this article has been developing nicely recently, as I had planned to work a bit more systematically on Nuclear magnetic resonance, MRI, Neuroimaging, DTI, fMRI in the near future. Since NMR spectroscopy is probably going to be the first approved MR article and thus basically sets the stage on how MR and related concepts are going to be presented here at CZ, I would like to have a bit more time to develop a coherent structure for this set of articles (preferably via the respective "related articles" subpages). As a first step in this direction, I just moved the "NMR principle" section to Nuclear magnetic resonance where it can be developed independently, without interfering with this one's approval (might be good to move the Catalog there, too).
  • I did not have time to go through the NMR spectroscopy cluster in detail but I think that at least the following points should be addressed before approving it:
  1. I miss mention of some relevant concepts (e.g. line splitting, magnetization transfer, hyperpolarization, remote detection, localized spectroscopy and chemical shift imaging) as well as mention of the respective contributions of prominent pioneers, at least the relevant Nobel prize winners (Stern, Rabi, Bloch, Purcell, Ernst, Wüthrich, and perhaps Mansfield/ Lauterbur, too) - some brief phrases and/or redlinks may do for the moment (I will help with that)
  2. Intrawiki linking from here should be made more coherent (I will help with that)
  3. The content on the subpages should be properly formatted (I will do this for the bibliography, as I am working on ref formatting anyway) and annotated
  • I have thus extended the deadline to Feb 2 and envision Sekhar, David and me as approving this cluster by then.

--Daniel Mietchen 01:24, 18 January 2009 (UTC)

  • Re: 1 : please see the nmr spectroscopy advanced tab for a brief mention of 'non-conventional' NMR spectroscopy techniques such remote detection. As this is an INTRODUCTORY article all concepts cannot be discussed in detail. I believe a stub should be added for each of the topics that you have mentioned. But that can be done later.
  • The concept of sensitivity enhancement by magnetization transfer has been introduced briefly in the Nuclear Overhauser effect stub (see also the advanced section). However, the more common methods of magnetization transfer using pulsed RF fields would be difficult to introduce, as the theory of pulsed RF NMR spectroscopy is not adequately developed at this level. Line splitting due to J-coupling is mentioned but line-splitting due to dipolar interactions is only very briefly mentioned in the 'Dipolar coupling and Noe' section. Specialized techniques such as chemical shift imaging require a stub of their own or a complete article. Also, I believe, and I think that D.E.Volk will agree with me that biomolecular NMR spectroscopy requires one or more complete and independent articles, to which this will be only an introduction. He has made a list of NMR experiments and EACH of these probably requires a minimum of a page.
  • The work of the pioneers is adequately referenced -- please examine the references section where references start with work of Rabi, Bloembergen, Pound, Purcell, Bloch, etc. I did not mention Stern in the beginning of the article (his work is referred to later in principles section now removed by yourself) because Rabi's molecular beam experiments were the first demonstration of Nuclear Magnetic Resonance (gotta start somewhere:-). Work of Ernst (in FTNMR and nD-NMR section) and Wuthrich (biomolecular NMR section) is also referenced. See the Applications of Magnetic resonance in Pharmacology, Physiology and Medicine section for references to pioneering work of Lauterber,Mansfield,Ernst,Lee on MRI. I have not mentioned the name of the pioneers in the text, but the work is adequately referenced if you examine the references that site the work. Assigning credit to pioneers has to be done with great care and can be controversial, e.g., though most people in the medical MRI field believe that Lauterber was the pioneer for MRI, it is clear that the unrelated work of Lee (Nobel96) and coworkers (published earlier than Lauterber's paper) not only introduced the concept of determination of spatial positions using field gradients but also successfully implemented it, though the focus of their work was on an unrelated topic (phase transitions in superfluid He). (A slight bias on my part in assigning credit is possible here as I was a student of Prof. Lee at Cornell.) I do not have access to the primary literature, and am writing this from {own memory/other sources from the internet/personal textbooks}, therefore I preferred not to become responsible for assigning credit explicitly -- credit was assigned implicitly by citing the relevant references at appropriate places in the text. Sekhar Talluri 16:05, 18 January 2009 (UTC)
  • the present article can be regarded as a compromise between introducing and explaining the essential concepts while keeping the length manageable and the level accessible to a newbie. However, the focus of this article is on the concepts of importance to solution NMR spectroscopy (primarily because this is what I am most familiar with) - a separate and complete article on solid state NMR spectroscopy and/or MRI would be complimentary and could introduce additional important concepts. Sekhar Talluri 07:08, 18 January 2009 (UTC)
  • In my opinion it would be best to start four articles: one introducing solution NMR spectroscopy (this one), one introducing solid state NMR, one introducing MRI and one introducing NMR instrumentation and non-conventional NMR techniques such as zero-field NMR, noise for excitation, remote detection, field cycling, ODNMR, hyperpolarization, SQUID based detection, Dynamic Nuclear Polarization, etc. And then when all are approved have a 'grand synthesis' page for 'introduction to magnetic resonance' either linking these articles or merging them together into a single coherent article with other related articles on ESR and quadrupole resonance. Such a bottom up approach is likely to result in many more articles that are quickly approved and made available in pieces while others are being developed. The end result would be the same as a top down approach which would require much more time than Feb.2, IF I am required to make any more substantial contributions (It took me 8.5 years to get my Ph.D!). However, this is only an opinion, I have no objection if you try it the other way round. Sekhar Talluri 07:46, 18 January 2009 (UTC)
I work on this only during holidays when my internet connection at home is working ( sometimes it works and sometimes does not!). Best wishes. Sekhar Talluri 09:33, 18 January 2009 (UTC)
  • I do not see any special advantage to removing the Principles section at this stage, unless the editors believe there are any FACTUAL errors in it. Based on my experience with students I believe that it would be beneficial to have several different versions - a canonical one, one at an advanced level and one at 'student' level. The citizendium wikis are certainly designed to handle different versions of an article at several different levels and all can coexist. Sekhar Talluri 16:05, 18 January 2009 (UTC) It is OK. Sekhar Talluri 16:43, 18 January 2009 (UTC)
I think our respective positions on these matters are quite similar. I agree that we should not explain all those effects or concepts in this one article, instead we should just develop an idea on where they (including the Zeeman effect) should preferably go in this wiki, keeping in mind that its structure can still develop (and diversify, so as to accomodate for different readership levels). Similarly, I have seen the work of the pioneers referenced but I assume a separate article like History of nuclear magnetic resonance or some such may be appropriate at some stage, and a properly placed redlink in this article might invite relevant contributions. I also agree that wikis are mainly bottom-up but since we at the bottom can talk to each other, we might end up with a relatively coherent idea on how the whole thing should eventually look like from the top. Since NMR seems to be a topic of wider interest than many of the articles I happened to bump in here, it seems to be worth using this occasion to find out how well bottom and top can go together. --Daniel Mietchen 10:00, 19 January 2009 (UTC)

Approval comment

Good to see you guys working this so well. Just to be clear, you can approve an article without its cluster if you like, but certainly feel free to get it all up to par. Also, as Sekhar is an author, we would either need another editor on board, or David can give his ideas here on the talk page and Daniel or Sekhar can collaborate with him here to get them into the article. That way he will be able to use the single editor approval method and we will know that all of you agreed with his content issues as you put them in. Others can help as well with content and copy edits. Make sure to update the version number once you are all agreed and then I'll return on February 2 to lock it down for you. D. Matt Innis 02:22, 18 January 2009 (UTC)

Why is Sekhar not an editor? I think his writing so far certainly did qualify him. As for approval, Paul said he would step in when needed, and I would certainly prefer the collaborative experience of editing alongside Sekhar, David and Paul on this one. --Daniel Mietchen 09:45, 19 January 2009 (UTC)
I believe his PhD has NMR in the title! He should at least be a specialist NMR editor. David E. Volk 14:28, 19 January 2009 (UTC)
He didn't apply to be an editor. Editors have different requirements, including things like CVs and a much more stringent verification, but certainly having recommendations from you guys sure helps! Sekhar, see this: apply as an editor. D. Matt Innis 01:06, 20 January 2009 (UTC)

Where is the Zeeman effect?

When I learned NMR the first thing I was told was the linear Zeeman splitting of the energy of a proton spin in a static magnetic field (plus the well-known picture where the radio frequency fits exactly between the α and β state energies, inducing a transition). Do we have that somewhere or is it not relevant anymore? --Paul Wormer 17:05, 18 January 2009 (UTC)

The Zeeman effect is due to electron orbital angular momentum and its associated magnetic moment. This article was titled Nuclear Magnetic Resonance spectroscopy hence I started with references to Nuclear Magnetic Resonance first demonstrated by Rabi in molecular beams; and later in static samples by groups of Bloch and Purcell. The different experimental methods for detection and measurement of nuclear magnetic resonance have not been covered in this introductory article. However a very brief discussion of current methods is present in the NMR spectroscopy->Advanced section. Sekhar Talluri 18:17, 18 January 2009 (UTC)
Regarding your second comment, the statement expected by you is present at the bottom of the last paragraph of the 'principles' section of the article submitted for approval which has now been removed by D.Mietchen to a separate article entitled 'Nuclear Magnetic Resonance'. Sekhar Talluri 18:17, 18 January 2009 (UTC)

Reply to Zeeman effect?

The Zeeman effect is due to electron orbital angular momentum and its associated magnetic moment. This article was titled Nuclear Magnetic Resonance spectroscopy hence I started with references to Nuclear Magnetic Resonance first demonstrated by Rabi in molecular beams; and later in static samples by groups of Bloch and Purcell. The different experimental methods for detection and measurement of nuclear magnetic resonance have not been covered in this introductory article. However a very brief discussion of current methods is present in the NMR spectroscopy->Advanced section.
Sekhar Talluri 18:00, 18 January 2009 (UTC)

Yes you're right, the s-electron of a hydrogen atom in a magnetic field gives the prototype Zeeman effect and it would be proper to start an EPR (not an NMR) article with that. The description of a spin-½ hydrogen nucleus in a magnetic field is so similar (a 2 × 2 secular problem based on two spin functions, linear in the magnetic field B) that I confused it with the Zeeman effect. In retrospect I learned about the nuclear spin-½ problem as the simplest NMR example possible. But as you know, the theory is exactly the same for both (nuclear and electronic) types of spin: increase B, one spin level goes up, one goes down and for a certain B-value the EM frequency matches the difference and a transition takes place. --Paul Wormer 08:38, 19 January 2009 (UTC)


I think we need articles for the following, not necessarily all in one cluster:

The big four

  1. Nuclear magnetic resonance (theory or advanced)
  2. NMR Spectroscopy - this will be generic 1D, 2D and 3D
  3. MRI
  4. Solid state NMR

The specific pages

  1. Protein NMR spectroscopy
  2. Nucleic acid NMR spectroscopy
  3. Solid state protein NMR
  4. Metabolomics (or Metabonomics)

List of NMR experiments

  1. this is nearly complete

The experiments - single pages for many widely used experiments

  1. HNCO
  3. HNCA
  4. etc etc etc

Advanced NMR topics

  1. Residual dipoolar coupling
  2. chemical shift anisotropy
  3. TROSY
  4. Product operator (NMR)
  5. etc etc etc

David E. Volk 14:40, 19 January 2009 (UTC)

Thanks, David, for providing this scheme. I have just converted it into CZ:Schema of Magnetic Resonance-related articles where we can perhaps more easily work on the structure. Please take a look, extend as you see fit, and comment there. With respect to the present article, it may be worth to consider moving it to Liquid-state NMR spectroscopy, which would more clearly define the scope and thus facilitate agreements on what should or should not be included. --Daniel Mietchen 16:21, 19 January 2009 (UTC)

Re: discussion above

Based on the discussion above, it appears that it would be usefull to have an article on Product Operator formalism in Citizendium. I will try to write an article describing the basic principles of the Product Operator formalism in May (when our vacation starts). There are two prerequisites for an article on Product Operator formalism - 1) Theory of Angular momentum (QM) and 2) Time dependent perturbation theory. An excellent article on Angular momentum theory is already present in Citizendium by Paul Wormer. However, there appears to be no article on perturbation theory. Hopefully, by May, there will be one - even a brief introduction to time dependent perturbation theory would be adequate - the application of perturbation theory in the context of Product Operator formalism for high-resolution NMR is quite straighforward. BTW, I hope that my comment regarding Pauli, Stern-Gerlach and Zeeman did not imply that their work is not relevent to NMR spectroscopy - their work certainly is relevant, because the theory of Nuclear and Electron Magnetic resonance is essentially the same - but it did seem feasible to write an internally self-consistent article on NMR spectroscopy without referring to their work - as I had mentioned earlier - we have to start 'somewhere'! Sekhar Talluri 17:42, 22 January 2009 (UTC)

I just noticed the article on NMR product operator formalism in citizendium started on 19th Jan. by D.E.Volk ! The schema of MR will certainly help us to find out what is available efficiently. Sekhar Talluri 13:56, 24 January 2009 (UTC)

Towards approval, again

A few points after having gone through the article (not yet the whole cluster):

  • I still think the current version does not really fit with the scope of the article (as suggested by the title), since important aspects like solid-state spectroscopy are missing. Besides, I do not see a need to hurry with approvals, also not with this one. However, given that this is the most advanced (in terms of writing) MR article here on CZ, it is perhaps good to continue working on this one (approved or not) and to export sections from there to the related articles on occasion, so as to keep this one at a manageable size.
  • The formatting still needs a lot of work; references and intrawiki links in particular but also the use of bolding and the placements of references in the text. Once this is done, it will also be easier to enter more information in the right place, so that the article can grow healthily. One side effect of the unconventional formatting is the "Summary" which I like as an idea but think it should be placed more prominently.
  • Some more illustrations would be nice; the COSY one would be more useful with axes indicated
  • To sum up, I do not feel comfortable approving this one but I see no harm if David does so. I really hope that this is a first step to more MR-related activity.

--Daniel Mietchen 07:47, 8 February 2009 (UTC)

Approval Comments

Hello All, the approval date has arrived. I see that Daniel has had some concerns and made some changes to the article since the January 17, 2009 version that David has marked in the ToApprove section of the metadata template. Since this is a single editor approval, I can only approve the version that David approved (unless they are only copy edits). I would feel more comfortable knowing that David was comfortable with Daniel's edits and we could approve the whole thing at once. We can always re-approve if we have to, however. I'll be back in about 8 hours to perform the approval, so you have some time. See you then.D. Matt Innis 17:22, 9 February 2009 (UTC)

I've been in touch with David through email and he tells me that he is unable to access the page until this weekend, so I will go ahead and approve the version that is dated for January that does not include Daniel's edits. Once David gets back this weekend, he can review the changes and ask me to update the version if he chooses and I will be able to update the approved version then. D. Matt Innis 00:47, 10 February 2009 (UTC)


Congratulations again! Version 1.0 is the January 17th version. We'll be glad to make any further updates as we get word. D. Matt Innis 00:56, 10 February 2009 (UTC)

format, etc

I agree with Daniel that this needs a lot of work yet. Eventually we need to address the following:

1) Some pictoral representations of NMR, ie a few vector diagrams and energy level diagrams.

2) Nice images of 1D, 2D and 3D spectra (near the very top), with section blowup in the 1D to show coupling patterns.

3) Removal of the QM equations to a separate advanced topics article. Most NMR practioners use product operator formalism and rarely use the QM or density matrix approaches, because the former is much simpler. So, I wouldn't expect to a complete novice to appreciate the QM equations. I think separate articles for Product operator and densiity matrix formalisms should be written, with some overlapping material in each to show how they can be related.

4) An image of an NMR spectrometer and an MRI spectrometer?

5) The article needs to be aimed at a more general audience at the beginning.

David E. Volk 16:32, 13 March 2009 (UTC)