Three-Bond Couplings CJ

Coupling constants on modem FT-NMR spectrometers are more easily determined by printing Hertz values directly on the peaks. It is a simple matter of subtracting these values to determine the coupling constants in Hertz. See, for example, the spectra shown in Figures 3.40 and 3.46, in which peaks have been labeled in Hertz. Section 5.2 in Chapter 5 describes the various types of coupling constants associated with two-bond ( 7), three-bond ( 7), and four-bond CJ) interactions. 

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