Varian UNITY INOVA NMR, Hardware Installation, Page: 58 / 65

6.3 Testing CRAMPS NMR
01-999044-00 C0501 UNITY INOVA Solids Hardware Installation
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2. Tamp down this sample carefully. Then add a small amount of adipic acid and tamp
the acid down.
3. Fill the rotor with more inert material and insert the cap.
4. Replace the benzene sample with the adipic acid sample. Do not retune the probe.
Put the probe in the magnet and spin the sample at 1550 Hz.
5. Run the procedure given in the section “Using MREV8 to Demonstrate Multipulse
Operation” on page 56 .
6. Set
tof
to the best value as determined in the MREV8 procedure and set the
following parameters:
np=512 tau=3.5 fn=4096 nt=1
.
7. Acquire a spectrum and check that it looks similar to the one in Figure 29 .
Note that the
dscale
values are wrong! Vary
tof
to get the best resolution of the
right-hand peaks.
8. Place a cursor on each peak of the doublet and enter
scalesw=sfrq/delta
to
set the scale factor.
9. Place the cursor on the right-most peak and enter
rl(2p)
to reference it. The
spectrum should now have resonances at 2, 3, and about 14 ppm, as in Figure 29 .
10. Save the FID for later reference, using
svf(file)
, where
file
is the name you
select for the file to hold the FID.
Running the BR24 Sequence
The resolution specification is made using another multipulse sequence called BR24. After
the MREV8 pulse sequence is working correctly, follow the steps below.
1. Enter
br24
to convert the parameters to run the BR24 pulse sequence.
Figure 28. Adipic Acid Spectrum