Sample: 0.0485M Triphenylphosphate (TPP) in acetone-d₆

Record a ³¹P spectrum.

The calibration of the ³¹P 90º pulse via the transmitter channel is performed using the standard ³¹P parameter set (the pulse program is zg). A ³¹P spectrum is repeated varying the pulse width (p1 at high power level pl1) until maximum and null points are found.

It is very important to use a long recycle delay, usually d1=5*T₁(³¹P) (for instance, d1=60 s).

From the TPP resonance we define the phase correction (using the phase subroutine) and plot region (using the DefPlot button) to be monitored. o1 is set on-resonance of the selected signal.

Start acquisition executing the AU paropt program. Answer the questions as follows:
 
             Enter parameter to modify:             p1
             Enter initial parameter value:          2
             Enter parameter increment:             2
             Enter # of experiments:                  16
 
In this case, paropt automatically acquires 16 spectra while incrementing the parameter p1 from 2 usec to 32 usec.

Each spectra is automatically processed with the defined lb value (usually lb=5) and for each value of p1, only the spectral region defined above is plotted. All spectra appear side-by-side in the corresponding procno 999. The first maximum value must be the 90º proton pulse. However, more carefully calibration is performed when you get nul the signal. At this point, the pulse would correspond to a 180º pulse. Further nulling must occur at 360 degree.