UNIVERSITY OF WISCONSIN River Falls

COSY-90 Instructions

Typical acquisition time = 20 minutes

COSY90 is a little noisier than COSY-45, but takes far less time. If your sample is fairly complicated, or requires suppression of diagonal peaks, you might be better with COSY-45 or other techniques.

Note: Where the instructions tell you to type a command, only type what is within the quote marks, do not type the quote marks.

1. Follow the initial steps of sample preparation, logging on, locking and shimming, that are used for a routine proton experiment.

2. Be sure that the probe is tuned to 1H.

1H REFERENCE SPECTRUM

3. Run a normal 1D proton spectrum. If you wish to change the scale, reset sw and sfo1 (the spectral width and center frequency of the spectrum) using the sw-sfo1 button and run again. Write down the name of the data set. The resulting file should be saved in your directory on the D: disk.

4. When finished, type sw in the command line and write down the displayed value. Do the same for sfo1.

5. Use the cursor to identify a reference peak (usually TMS but might be a solvent or known sample peak) and write down the value of this peak.

6. Select Output --> show-define --> retain CX

RUNNING THE 2D EXPERIMENT

7. Turn the spinner off.

8. Select File --> New and open a new file in your directory.

9. At the command line type "rpar cosy". This will load standard COSY-90 parameters.

10. Type "eda" (return). Find SW and click in the box under F2 and enter the SW value for your reference 1H spectrum. Then enter the same value for the SW under F1. Click on "save".

11. Type "sfo1" (return) and enter the sfo1 for your 1H spectrum. (return).

12. Type "sfo2" (return) and enter the sfo1 for your 1H spectrum. (return).

13. Type "rga" (return)

14. Type "zg" (return).

PREPARING FOR PLOTTING

15. Type "edg". Click on "EDPROJ1". Find PF1NAME and enter the name of the 1H dataset and user name that you recorded earlier. Click on "save". Make sure that you have the disk unit D: correct.

Click on "EDPROJ2". Find PF2NAME and enter the name of the 1H dataset and user name that you recorded earlier. Click on "save" and again on "save" to exit "edg".

PROCESSING

16. Type "xfb" (return). The 2D spectrum will be displayed.

17. Use the "*2" and "/2" buttons to adjust the amplitude to display the spectrum appropriately.

18. Click on "calibrate" and obtain cross hairs on the screen. Move the cross point to a point on the diagonal that coresponds to the reference value on each spectrum that you recorded earlier. Click the center mouse button and enter the reference values.

19. Pull down from "output", move to "define-show..." and release on "current screen limits". Respond to the displayed values with three returns.

20. You can type "setti" in order to put a title on the spectrum, but the title may get written on top of the horizontal 1H spectrum projection.

21. Type "view" (return) to obtain a preview of the plot. (Quit.)

22. Type "plot" (return) to plot.

LOGGING OUT

Log out in the usual manner.

IMPORTANT: Put a standard sample back into the spinner and release the lift button on the keypad. You may also turn on the spinner. Do not leave the magnet with the lift air on and no sample in.