Energy levels of spin

B, via the bonding electrons. The energy level of spin A depends on the orientation of spin B, so two spectral lines are generated. The magnitude of the interaction is given by the spin-spin coupling constant /ab which is expressed in hertz and is independent of the applied field. 

Figure 1 Space quantization and energy levels of spin-5 and spin-1 nuclei. (A) and (C) spin- (B) and (D) spin-1. The energy level splittings produced by an applied magnetic field depend on the value of the gyromagnetic ratio, y (here taken as positive).

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