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PARAMETER SETInsert 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 and change the pulse program to secsyqf can be visualized in the PulsProg section or with the edcpul command).MODIFY SPECIFIC PARAMETERS
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.ACQUISITION
Set nd0 to 2.
Modify o1p and 2 sw values accordingly. 1 sw can be set to a smaller value (2-4 ppm) because cross-peaks are displayed about an axis of 135 degree relative to F1=0 Hz axis. For instance,
o1 1700 (enter)
2 sw 8 (enter)
1 sw 3 (enter)On the other hand, the values of TD2 and TD1=NE are set, by default, to 1K and 128w, respectively. The SECSY experiment allows to use a more reduced data matrix by reducing TD1=NE. 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).PROCESSING
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.PLOT
Use the TOPSPIN plot editor (xwinplot)OBSERVATIONS
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_getlcosyp)) 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_2d).OTHER RELATED VERSIONSThis experiment can also by recorded in full automation mode using macros (edmac), BUTTON-NMR (buttonnmr) or ICON-NMR (iconnmr)
Written by Teodor Parella Copyright © 1998-2008 BRUKER Biospin. All rights reserved. |