This two-dimensional absolute-value HOM2DJ
spectrum shows (decoupled) chemical shifts on one 2D axis and coupling
constants along the other 2D axis. Before setting up the HOM2DJ experiment, see
Acquiring and Processing 2D Experiments. See the Varian Guide to NMR
Experiments for a complete description of this experiment.
1.
Join
the experiment in which the 1H reference spectrum was collected.
Type hom2dj.
2.
Type
dg. Adjust the parameters listed below for the standard HOM2DJ:
·
sfrq=set
by spectrometer
·
dm=’n’
·
tn=’H1’
·
sw1
= 8 to 48
·
at
= set by spectrometer
·
ni =
4*sw1 (thus, resolution = ¼ Hz)
·
np=2048
·
dp=’y’
·
sw = sw from 1H reference spectrum
·
hs=’n’
·
ss=2
·
phase=0
·
tpwr = listed at console
·
pw = 1H 90° pulse width
·
p1= 1H 180° pulse width
·
d1 = 1H relaxation delay (1-2 * 1H T1)
·
d2=0
·
rf1 = rf from 1H reference spectrum
·
rfp1 = rfp from 1H reference spectrum
·
tof = tof from 1H reference spectrum
·
wp1 = wp from 1H reference spectrum
·
nt = multiple of 16
·
sp1 = sp from 1H reference spectrum
·
ct
= set by computer
3.
Change
ni, nt, and d1 to suit your scheduled time (see table page 2).
The vertical (non-acquisition) resolution equals sw1/ni.
Typical values are listed
below:
|
d1 |
ni |
nt |
Time |
Vertical resolution |
|
1.5 |
128 |
4 |
0:15 |
17.2 Hz |
|
1.5 |
256 |
4 |
0:31 |
8.6 Hz |
|
1.5 |
512 |
4 |
1:02 |
4.3 Hz |
|
1.5 |
128 |
16 |
1:01 |
17.2 Hz |
|
1.5 |
256 |
16 |
2:03 |
8.6 Hz |
|
1.5 |
512 |
16 |
4:09 |
4.3 Hz |
|
1.5 |
128 |
64 |
4:03 |
17.2 Hz |
|
1.5 |
256 |
64 |
8:10 |
8.6 Hz |
|
1.5 |
512 |
64 |
16:37 |
4.3 Hz |
|
2.25 |
128 |
4 |
0:21 |
17.2 Hz |
|
2.25 |
256 |
4 |
0:43 |
8.6 Hz |
|
2.25 |
512 |
4 |
1:28 |
4.3 Hz |
*** TURN OFF THE SPINNER***
Type au to start the
acquisition.
Processing, Displaying, and Plotting:
Process using the procedure for Processing
a 2D Absolute-Value Experiment. Plot pos.only contours. After
processing, type rotate(45.0). The command foldj can then be
typed to symmeterize the spectrum.