Insert the sample (ij).

Choose the solvent deuterium signal with the lock command

Tune and match the probehead (wobb or atma if required).

Optimize the shim procedure (read an optimized shim file with the rsh command or performs a gradshim if required).

Record a conventional ¹H spectrum. Note the o1p and SW values to optimize spectral widths in the corresponding 2D experiment.

Create a new dataset (new) and read the standard BRUKER parameter set (rpar) to record a 2D ¹H-¹H COSY-45 spectrum with rpar COSY45SW all (the pulse program cosyqf45 can be visualized in the PulsProg section or with the edcpul command).

On the other hand, only change the pulse program to cosyqf90 if a COSY90 experiment is desired.

It is generally recommended that COSY experiments be run without sample spinning. Update the corresponding pulses and power levels in the acquisition parameters according to the selected solvent/probehead parameters by executing the getprosol command (pulses and power levels must be correctly set by the edprosol command). If required, any acquisition parameter can be modified manually or in the AcquPars section.

Otherwhise, the required acquisition parameters can be displayed with the ased command. Modify the following parameters accordingly:

• o1p is the center of the spectrum
• 2 sw is the spectral width in the F2 ¹H dimension
• 1 sw is the spectral width in the F1 ¹H dimension
• 2 td is the time domain in the F2 dimension (usually set to 1K-2K)
• 1 td is the number of experiments/increments to be recorded in the F1 dimension (usually set to 128w-256w)

Finally, set the number of scans as a function of the sample concentration (by default, ns 8 and ds 4).

Start acquisition by rga and zg (the expected experimental time is displayed with the expt command).

Process the recorded data with xfb. By default, SI2=SI1 and non-shifted sine-bell window functions (WDW2=WDW1=SINE) are applied to both dimensions (SSB2=SSB1=0) using MC2=QF. The final magnitude mode spectrum no need for phase correction.

The resulting 2D spectrum can be also optionally symmetrized by using the sym command.

Use the TOPSPIN plot editor (xwinplot)

It can be advisable to store all acquisition and processing parameters (with the command wpar) to be used later.

Both acquisition and processing steps can be performed using predefined automated AU programs. In this case, start data acquisition with the xaua command (the program executes the AU program defined in the acquisition parameters AUNM (au_getlcosy)) and the data can be automatically processed and plotted with the xaup command (the program executes the AU program defined in the processing parameter AUNMP (proc_2dsym).

This experiment can also by recorded in full automation mode using macros (edmac), BUTTON-NMR (buttonnmr) or ICON-NMR (iconnmr)

List of Related Experiments:

Phase-cycle COSY experiments
Gradient-enhanced COSY experiments