Bruker BioSpin Solid State NMR, User Manual

Page: 65 / 328

Basic Setup Procedures
User Manual Version 002 BRUKER BIOSPIN 65 (327)
The figure above is an example of where the probe is either tuned to a completely
different frequency outside this window or the probe is not connected to the se-
lected preamp. Check
edasp
for correct routing, Check for correct matching box
frequency range. Increase WBSW to 50 or 100 and try to find the probe reso-
nance position.
When the probe is tuned well, as shown in
Figure 4.6.
, start an acquisition by typ-
ing zg in the command line or clicking on the black triangle (upper left side) in the
acquisition display. Do a Fourier transformation and a phase correction by typing
ft and phase correct.
Set offset
O1
to the value obtained for the center peak (see
Figure 4.13.
) and
start “
xau angle
” . This will allow you to view the fourier transformed spectrum or
the FID after
ns
scans. The magic angle is adjusted best when the spikes on the
FID or the spinning sidebands in the Spectrum display have maximum size, like
shown in
Figure 4.9.
. This is most easily seen with the carrier exactly on reso-
nance and the un-shuffled FID display mode. The spinning sidebands should
have maximum intensity, the rotational echoes on the FID should extend out to at
least 8msec in the FID-display.
Figure 4.9. FID and Spectrum of the
79
Br Signal of KBr used to Adjust the Magic
Angle
Calibrating 1H Pulses on Adamantane 4.3
Spin the KBr sample down and change to a spinner filled with adamantane. Spin
at 5-10 kHz. Generate a new data set from the KBr data set by typing
new
. Set
the instrument routing for
13
C observe and
1
H decoupling, as shown in the follow-
ing figure: