Bruker BioSpin Solid State NMR, User Manual

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146 (327) BRUKER BIOSPIN User Manual Version 002
Proton Driven Spin Diffusion (PDSD)
2D Experiment Setup 11.2.1
8. Type iexpno to create a new data file and switch to the 2D mode using the
“123” button. Load the pulse program cpspindiff.
9. Recheck pulse widths and power levels, using ased .
10. Go into eda and set parameters for sampling in the indirect dimension, the
spectral width 1 swh . Note, that in TopSpin 2.1 or later the parameter IN_F1 re-
places the parameters in0 and nd0 . Usually, 1 swh equals swh . Choose a suit-
able spin rate such that no RR condition occurs and sidebands do not overlap
with peaks, if possible set the sweep width in F1
1 swh equal to the spin rate or
such that sidebands folding in along F1 do not interfere.
11. Make sure the correct nucleus is selected in the F1 dimension; make sure to
choose an appropriate quadrature detection mode in FnMode (usually
STATES-TPPI).
12. Choose the appropriate sampling time ( td1 ) so that the required resolution ( FI-
DRES ) in the indirect dimension is achieved.
13. Set the desired mixing time as
d8
. The required multiple of spin periods (from
cnst31
) is calculated as
l1
, the real mixing time may deviate by fractions of a
rotor period. The required mixing time may vary widely depending on the sam-
ple properties, from a few milliseconds to hundreds of milliseconds, if long dis-
tance correlations in a mobile sample need to be observed. Note that longer
mixing times will result in S/N deterioration, as the mixing time approaches the
T
1
of the observed nuclei.