How to process Varian DEPT spectra?


This tutorial shows you how to process a Varian DEPT spectrum using Mnova software. As you well know, the DEPT pulse program in Varian generates a stacked plot with four slices, acquired with phase of the last pulse equal to 45, 90, 90, 135 degrees. When you load this kind of spectra into Mnova, you will obtain something like this:


As you can see, you will have in the first slice (red slice with final pulse: 45 degrees) all the protonated signals, in the second and third slices you will get only the CH signals up and in the forth slice (purple slice with final pulse of 135 degrees) a spectrum with the CH and CH3 up and the CH2 down Then, please make sure that the phase of all the slices is right. Otherwise you will need to apply a phase correction. We recommend you to select 'Active spectrum' in the sixth button of the left-vertical toolbar:

While working on this mode, you will see on the screen just the active spectrum (the spectrum which is highlighted in green in the stacked plot). Should you want to move to another spectrum without resorting to the stack mode just press Shift+Mouse Wheel or Shift + Up/Down keys. We are going to correct slightly the phase of the first slice (the phase of the other slices will be automatically corrected):


IMPORTANT: Remember that even if only the active spectrum is visible, unless the “Apply Processing to All spectra in Stack” option is off, all spectra in the stack will also be processed. Finally, follow the menu 'Processing/Arithmetics' and enter the following formula:


Please bear in mind that you can save this formula by using the 'Save' button    .  Apply the arithmetic formula to obtain all the protonated carbons in the first slice (red), the CH in the second slice (green), the CH2 in the third one (blue) and the CH3 in the forth slice (purple), as you can see in the picture below:


Note that he relative intensities of the signals are not exactly the same in all the slices, so you might obtain small residues in some of the slices.


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