Basic Bruker C13 NMR Tutorial
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At the Xwinnmr command line, type 'ft' and press Enter. The display will switch to the data
processing screen and display a Fourier transform of the FID.
AUTOMATIC PHASE ADJUSTMENT:
At the Xwinnmr command line, type 'apk' and press Enter.
MANUAL PHASE ADJUSTMENT:
Click on the 'Phase' button on the left of the screen. To adjust the phase manually, click and hold on the 'ph0' button and move the mouse vertically. You can see the spectrum phasing change in real time. When the phasing is correct, release the mouse button. Clicking and holding on the 'ph1' button will allow finer adjustment of the phasing and baseline.
When phasing is complete, click on the 'Return' button and choose 'Save and Return' to save
your changes.
EXPONENTIAL MULTIPLICATION:
Usually you will need to apply an exponential multiplication function to the FID to reduce the noise level in the baseline. At the Xwinnmr command line, type 'lb' and press 'Enter'. The current Line Broadening (LB) factor is displayed. Generally, values ranging from 30 to 60 Hz will be useful. Enter the new value in the LB field and press 'Enter'.
At the Xwinnmr command line, type 'em' and press 'Enter'. Because the exponential function is applied to the FID, you now have to Fourier transform and re-phase the spectrum.
Continue changing the LB factor and applying the exponential multiply until the baseline noise is
at an acceptable level. Note that if LB is increased too much, detail will be lost in fine peak
splittings and shoulders.
AUTOMATIC INTEGRATION:
At the Xwinnmr command line, type 'abs' and press Enter. Click on the 'Integrate' button on the
left of the screen. Click on the 'File' menu and choose 'Read intrng' to load the automatic peak
integrations. You will now see the peak integrations above the peaks. If the integrations are
satisfactory, click on the 'File' menu and choose 'Save as integr & return' to exit the integration
tool.
MANUAL INTEGRATION:
Click on the 'Analysis' menu and choose 'Auto integration'. Click on the 'Integrate' button on the left of the screen. Click on the 'File' menu and choose 'Read intrng' to load the automatic peak integrations. You will now see the peak integrations above the peaks.
Select a peak to modify by clicking near the right edge of the integral. A star will appear when the integral is selected. Delete the integral by clicking the 'delete' button in the 'current' grouping at the left of the screen. Integrate the peak by clicking the left mouse button which places a moveable cursor on the spectrum baseline. Move the cursor to where the integral should start, then click the middle mouse button. Click the middle mouse button again where the integral should end. The new integral will appear above the peak. Repeat this process for all peaks which require re-integration.
The integrated value of a selected peak can be specified by clicking on the 'calibrate' button on the left of the screen and typing in a new value. All other peaks will be automatically recalculated.
The integrals can be resized by clicking and holding on the resize button (both up and down arrows) and moving the mouse vertically. Resizing can be done in either the 'current' or 'all' button groupings.
When the integrations are satisfactory, click on the 'File' menu and choose 'Save as integr &
return' to exit the integration tool.
PEAK PICKING:
This section is not yet complete...