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PARAMETER SETInsert the sample. Choose the solvent deuterium signal with the lock command. Tune and match the probehead. Optimize the shim procedure (read a shim file with the command rsh if required). Record a conventional 1H spectrum.
Create a new dataset with edc or, alternatively, increment the experiment number with the iexpno command from the reference 1H spectrum and change the pulse program to ledgp2s1d (it can be displayed with the command edcpul).MODIFY SPECIFIC PARAMETERSSet the following gradient parameters:
Gradient ratios: gpz6 1-100, gpz7 -13.17, and gpz8 -17.13.The diffusion and the eddy-current times are d20 and d21. Standard value can be 200 and 50 ms, respectively.
Gradient Lengths: p30 1 ms and p19 1.1 ms.
Recovery delay: d16 100u.
Set the number of scans as a function of the sample concentration (fos instance, ns 8 and ds 16).ACQUISITIONRepeat the experiment increasing the gradient strength (gpz6) (the gradient length (p30) can be also varied). The diffusion time value (d20) can also be modified to obtain other series of 1D spectra.
Start the first acquisition by rga and zg (the expected experimental time is observed with the expt command). All other acquisitions will use the same rg value.PROCESSING
Process the first recorded data with ef (lb=1) and phase to pure absorption. The same phase correction is applied for will be applied in all remaining spectra.PLOT
Use XWINPLOT.OBSERVATIONS
It is advisable to store acquisition and processing parameters (for instance, with the command wpar led1d all) to be used later.OTHER RELATED VERSIONSAlternatively, you can perform the acquisition and processing steps of this experiment using predefined automated AU programs (See 2D DOSY for more information) by defining the pulse program to ledgp2s (it can be displayed with the command edcpul).