I have a DEPT analysis problem.

[hyildirim]

I have taken a DEPT spectrum of an organic sample.
It has 4 spectras that are all protonated carbon, CH, CH2 and CH3.
They especially CH,CH2, and CH3 spectras should be different but CH and CH2 spectras are same.
What can I do to separate CH and CH2 peaks? Could you give me any suggestion?

 

[Lok]

http://en.wikipedia.org/wiki/Carbon-13_NMR#DEPT_spectra

The separation is done by varying "the tip angle of the final 1H pulse" (reasonably put).

 

[chemisttree]

You will need to perform an experiment to determine the 90 degree pulse width for the CH proton and from that calculate the 45 degree pulse width. That needs to be fairly accurate and you need to put in a pulse delay 10X the longest decay constant for the slowest recovering proton... another experiment for that. Be sure the proton decoupler is not on continuously as well while you acquire the FID.

 

[hyildirim]

Thanks for your helps..
best regards