AMMRLers
In response to my query about using DEPT for 29Si according
to "150 & More..." I got several responsents who suggest it
does not work in their hands either. (Several suggested that
degassing might help but it seems the T1 and T2 are plenty
long in my sample..could affect polarization transfer rates
I suppose.)
The solution came from Charlie Fry (UWisc):for him refocussed
INEPT worked well as the delays are shorter and this is
important for small J values. (He also pointed out a factor
of 0.5 error in Berger's calculation of d3opt.)
I set up the refocussed INEPT and got a WHAMMO big signal,
of about 5x the normal decoupled 29Si. I did have to play
with the J value a bit (8 vs 7Hz) and adjust Bruker's cnst11
and put a factor of 0.5 in the Bruker ineptrd program delay
calculation to optimize but it seems straightforward. What
an immense time saver!
As this works I have still not troubleshot the DEPT problem
nor even tried degassing but I am sure there is room for
some development on that.
Anyway, thanks to all who responded. I send this to all because
many labs do Si29 from time to time and might need to know of
this difficulty.
Another great example of the usefulness of this network:
Thanks Rich for all the support you do on this!
Think Peace Anyway
C Dickinson
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Received on Thu Jul 10 2003 - 17:03:35 MST