2D HET2DJ Experiment

 

This two-dimensional absolute-value HET2DJ spectrum shows (decoupled) 13C chemical shifts on one 2D axis and 13C-1H coupling constants on the other 2D axis. Before setting up the HET2DJ experiment, see Acquiring and Processing 2D Experiments. See the Varian Guide to NMR Experiments for a complete description of this experiment.

Acquiring the experiment:

1. Join the experiment in which the 13C reference spectrum was collected. Type het2dj.

2. Type dg. Adjust the parameters listed below for the standard HET2DJ:

·        sfrq=set by spectrometer

·        tn=’C13’

·        at = set by spectrometer

·        np=2048

·        sw = sw from 13C reference spectrum

·        ss=2

·        tpwr = listed at console

·        pw = 13C 90° pulse width

·        pp = 1H decoupler 90° pulse width (from shim sheet)

·        pplvl= 1H decoupler pulse power (from shim sheet)

·        d1 = 1H relaxation delay (1-2 * 1H T1) or ~1.5

·        d2=0

·        tof = tof from 13C reference spectrum

·        nt = multiple of 16

·        ct = set by computer

·        dn=’H1’

·        dof = tof from 1H reference spectrum

·        dm=’ynny’

·        dmm=’wcw’

·        dmf=9468

·        dpwr= 35

·        sw1 = C-H coupling (~ 200)

·        ni = set using time for experiment (see table below)

·        dp=’y’

·        hs=’nn’

·        reffrq=reffrq from 13C reference spectrum

·        wp1=sw1

·        sp1= -sw1/2

·        temp = 25 su

 

***TURN OFF THE SPINNER***

 

 

 

 

 

 

 

Change ni, nt, and d1 to suit your scheduled time.

The vertical (non-acquisition) resolution equals sw1/ni. Typical values are listed below for sw1=25000:

d1

ni

sw1

nt

time

vert. res

d1

ni

sw1

nt

time

vert. res

1.5

32

128

16

0:14

4.0 Hz

1.5

32

128

64

0:57

4.0 Hz

1.5

96

128

16

0:49

1.33

1.5

96

128

64

3:17

1.33

1.5

192

128

16

1:58

0.67

1.5

192

128

64

7:51

0.67

1.5

32

512

16

0:13

16.0

1.5

32

512

64

0:54

16.0

1.5

96

512

16

0:42

5.33

1.5

96

512

64

2:49

5.33

1.5

192

512

16

1:29

1.50

1.5

192

512

64

5:56

1.50

 

3.      Make sure the spinner is off, then type au to start experiment.

 

Processing, Displaying, and Plotting:

Process using the procedure for Processing a 2D Absolute-Value Experiment. Plot Pos. only contours.