Info

If all three experiments are run on the same sample, simple linear combinations of the three spectra (s1, s2, and s3) can be generated, which are "pure subspectra": one containing only CH carbon peaks, another containing only CH2 carbon peaks, and a third containing only CH3 carbon peaks. Generally, the 90° pulse experiment (spectrum 2) is run with twice the number of transients as the others (or simply run twice and added together) so that its signal-to-noise ratio will be comparable to the others. The precise weightings are shown below:

(D) 0.854*(s1) + 0.25*(s2) - 0.146*(s3) = all three types together

The predicted signal intensities and noise levels can be calculated from the weighting in the above equations, giving equal signal-to-noise in the three pure subspectra:

0 0

Post a comment