My problem was that I wanted to run 139La NMR experiments on our Bruker 600
Avance III HD and that there was no entry for 139La in edprosol. Some people
asked me if 139La was in ednuc and, indeed, it was. Then, there was the question
of feasability of 139La NMR. Some people told me to check if the preamplifier was
a 2HS (which stands for 2H stop) or 2HP (which stands for 2H pass) and I was told
that if the preamplifier is 2HS, it is unlikely that 139La but also 6Li, 9Be and
209Bi NMR will be possible. Our preamplifier is 2HS but I was able to run 139La
NMR experiments. The important point to know what is possible to do with your
spectrometer/probe is to check the coil properties with the edprobe command.
We have a BBO probe, so coil 1 is the BB coil and I read the folowing sentence
in the coil properties of coil 1:
Connector 1: 19F-109Ag
So, according to the coil properties of the probe, 139La but also 9Be, 6Li and
209Bi NMR are possible. I was then able to tune the probe but when trying to
acquire I ran into the issue of a lack of valid cortab for 139La.. However,
it is possible to create a peak power entry in cortab by selecting new experiment
and then BLA power definition without measurement. The correct routing has then
to be defined and a value por the peak power entered. Oversetimate this, because
without cortab all powers below the maximum will be underestimated because of the
compression of the amplifier - e.g put in 800W for a 300W amplifier, where the
peak power could be really 400W. The person who explained that to me was also
thinking that this will allow you to work with powercheck disabled but, in my case,
powercheck was anyway disabled in cf.
Having done this, I could acquire a 139La NMR spectrum of the reference LaCl3 in D2O.
To start with, I used the power indicated in edprosol for 17O, i.e. 150W. I found a 90
degree pulse of 10.5us. And I was able to acquire nice 139La NMR spectra with 8192
scans and a relaxation delay of 100ms for one of our student here at Queen's
University Belfast.
Received on Sun Oct 23 2022 - 16:08:11 MST