i like this post (click again to cancel)
1
i dont like this post (click again to cancel) remove favorite mark from this question (click again to restore mark)

Dear Everyone

I´d like to run 33S-NMR experiments using a Bruker NMR spectrometer at 400 MHz buy I nedd the pulse sequence name on the spectrometer. Someone know what is the pulse sequence for this experiment?

Thanks in advance

Juan Carlos

asked Jun 14 '12 at 08:41

Juan_Carlos's gravatar image

Juan_Carlos
11


One Answer:
i like this answer (click again to cancel)
3
i dont like this answer (click again to cancel)

Assuming you're working in solution, in principle simple zg pulse program is all that you need. There is no standard parameter set for 33S, however, because the sensitivity is very low and you will have very significant quadrupolar broadening, so there has been extremely limited use of 33S nmr. The quadrupole moment is higher than that of 14N, which is itself rather difficult to observe in all but very small or symmetric molecules. The sensitivity at natural abundance is at least 10x worse than carbon, even without allowing for fact that the broad lines will reduce sensitivity even more.

For setup, (NH4)2SO4 or 2M Cs2SO4 in D2O come at about 0ppm, whilst CS2 comes at -333ppm. You want to use a short acquisition time and short D1, perhaps 0.05s for the standard and even less for real compounds, so at least you can collect a large number of scans relatively easily. There are a couple of example spectra of the standards at http://chem.ch.huji.ac.il/nmr/techniques/1d/row3/s.html -real samples will be somewhat broader even than CS2, and may be too broad to see. Elevated temperature and low viscosity solvents may help for the real samples.

If you are working in the solid state, Cement and Concrete Research 36 (2006) 1781 – 1783, has some interesting results, but at much higher field (900MHz for proton), which makes things vastly easier in solids.

What sort of samples are you looking at?

link

answered Jun 15 '12 at 07:53

Pete%20Gierth's gravatar image

Pete Gierth
401

Your answer
Please start posting your answer anonymously - your answer will be saved within the current session and published after you log in or create a new account. Please try to give a good answer, for discussions, please use comments and please do remember to vote (login to vote)
toggle preview

powered by CNPROG