
Dual and Dual Broadband NMR Probes
10
Dual and Dual Broadband NMR Probes Installation
01-999124-00 J 0606
a.
Enter
r1=xx/5
, where
xx
is the specified pw90 specification for the probe.
b.
Enter
array('pw',20,r1,r1)
to create a pw array covering
approximately 360 degrees of nutation.
12. Enter
ga
.
13. Enter
dssh
after the last spectrum.
14. Determine
pw
form the first minimum.
This is the 180
°
pulse and the 90
°
pulse is one-half the 180
°
pulse.
15. Write the results for each probe in the forms provided in
16. Note the results for use in the
15
N sensitivity test.
1
H Spinning Resolution & Lineshape
This test measures the 50%, 0.55%, and 0.11% levels of the CHCl
3
sample. This test and
the
1
H spinning sidebands test (the next test) must be passed simultaneously.
1.
Put the appropriate CHCl
3
sample in the probe and spin it.
2.
Enter
rtp('/vnmr/tests/H1lshp')
nt=1 vs=1000
su
to set up the
system hardware.
3.
Enter a value for
pw
appropriate for your sample:
4.
Enter
ga
to acquire the spectrum.
5.
Phase the spectrum and plot it using
wp=250
.
6.
Normalize the spectrum, enter
vs=10k
, and plot the expanded
spectrum.
If floor vibration results in excessive
noise around the base of the peak,
nt
can be changed to a larger value
(e.g.,
nt=4
or
nt=16
); however, if
extreme vibrations are present, it
may be impossible to measure the
lineshape accurately.
7.
Measure lineshape as the linewidth
of the CHCl
3
peak at 50%, 0.55%,
and 0.11% of the main peak
amplitude, refer to
8.
Write the results for each probe in the forms provided in
1
H Spinning Sidebands
This test and the
1
H lineshape test (the previous test) must be passed simultaneously.
1.
Using the appropriate CHCl
3
sample, measure the
1
H spinning sidebands on the
same spectrum as
1
H lineshape.
Sample (Part No.)
Value for
pw
1% CHCl
3
(00-968120-89)
90
°
pulse
5% CHCl
3
(00-968120-99)
90
°
pulse
20% CHCl
3
(00-968120-76)
20
°
pulse
Figure 2.
1
H Lineshape Spinning
Measurement
Hz
-120
-100
-80
-60
-40
-20
0
20
40
60
80
100
120
140
13
C satellite
13
C satellite
CHCl
3
peak
0.11%
0.55%