# Can all NMR spectrometers perform special techniques such as COSY, NOESY, HETCOR,..? [closed]

Do you need special spectrometers for:

• probing nuclei other than hydrogen or carbon?

• performing 2D spectroscopy such as COSY, NOESY, HETCOR, HSQC,..

Or are these techniques usually available on standard NMR spectrometers?

• Can you give a bit of a background for this question? It would seem strange that you don´t know the answers (or have an expert at hand to ask) if you know these techniques and are thinking about using them. – Karl Mar 22 '20 at 14:46
• What do you consider a standard NMR spectrometer? Could you be more specific (it depends on the probe in the instrument, e.g. triple resonance probe)? – Karsten Theis Mar 22 '20 at 15:05
• @Karl I agree with you that the question as such rises indeed the (meta) question about the background of the OP. On the other hand, there is a wide spectrum (no pun intended) of groups. Some still drop the NMR tube in a card-board box and basically await the spectrum to be physically printed; others expect each member pass an introduction and then to record 1D/2D, Hoye's no-D and kinetic NMR on their own. Speculation: maybe the OP transients to such a later group. – Buttonwood Mar 22 '20 at 15:12
• @Buttonwood Of course, it´d just be good to know about that, to give an answer that actually fits. I hate preparing a talk for an unknown auditorium. ;) – Karl Mar 22 '20 at 15:16
• @Karl I aggree. – Buttonwood Mar 22 '20 at 16:13

It depends on a lot of things, software-wise

• some of these techniques are simply a software option
• you can implement pulse sequences yourself, if that´s possible with your control software
• you need to have the right software to transform and evaluate the data
• ... or write it yourself (not exactly rocket science if you know your way with Matlab/Octave etc.)

• you can have several probes for one spectrometer
• they can be single channel, or dual ("HX" usually), triple ... channel
• the "X" channel can be tuneable over a wide(r) range, or you are limited to e.g. carbon
• of course you need a transceiver with enough channels, which can be used at the wanted frequencies
• and a suitable preamp for every channel
• some techniques need more special hardware, like CPMAS, pulsed gradients, cryo etc.
• low field spectrometers on the market (afaik) have no user exchangable parts, so you are stuck with the hardware you bought

But to answer your immediate question: I guess with basically any living (as in "not undead") spectrometer, all those you named above should be possible, provided you can tune the X channel to the het nucleus you are after. They are the basic standards.

If you want to know a lot more, 200 and More NMR Experiments by Berger and Braun is probably your book.

There are multiple aspects to consider here.

• In terms of the magnet, the ones suitable to record a $$300$$ or $$500\, \pu{MHz}$$ $$\ce{^1H}$$ NMR spectrum may be well used to record 1D or 2D homo- and heteronuclear spectra as well.
• Other nuclei than $$\ce{^1H}$$ or $$\ce{^{13}C}$$ routinely are recorded in 1D with these standard spectrometers as well; for example $$\ce{^{15}N}$$, $$\ce{^{19}F}$$, $$\ce{^{31}P}$$ often relevant in samples equally relevant for biochemistry (heterocyclic chemistry, proteins); or inorganic chemistry (e.g., $$\ce{^{117}Sn}$$, $$\ce{^{119}Sn}$$, $$\ce{^{195}Pt}$$).
• Recording spectra with nuclei other than H and C however often is performed with dedicated probeheads. As an example, you are used that DEPT-135 / DEPT-Q / APT spectra are recorded to seemingly yield singlet signals only by proton broadband decoupling. A standard two-channel probehead however is not designed to equally decouple $$\ce{^{19}F}$$ beside $$\ce{^{1}H}$$, for example, and consequently your 1D $$\ce{^{13}C}$$ spectrum still show the couplings with $$\ce{^{19}F}$$:

(source)

An other example is recording NMR spectra for three types nuclei at once by triple resonance with three scales, as seen in biochemistry to elucidate protein structures. (An entry to this vaste topic might be Wuethrich's Nobel lecture 2002, here.)

(source)

Displaying only the mount of the heads still visible on the bottom of the NMR magnet, this would not be possible with a standard probehead:

(source)

but would recorded comfortably with a triple-resonance head like this

(source)

• Recording NMR spectra requires adjustment of pulse sequences (e.g., delay times and phases). Typical parameters are literature known (e.g. APT for $$\ce{^{13}C}$$ in the Journal of Magnetic Resonance), so the software of the spectrometer may internally look up and adjust thes for the more frequently used ones experiments. Occasionally, you find blogs about these techniques, too (e.g., University of Ottawa, PNA)

• Can you check the first sentence in your last point, I can´t make head or tail of it. ;) – Karl Mar 22 '20 at 15:23
• @Karl Indeed, the phrase required an edit. – Buttonwood Mar 22 '20 at 16:14