Leaning multiplets

NMR pulse sequence without getting tied up in the details of pulse phases and a mountain of sine and cosine terms only the essential elements of the sample net magnetization will be described at each point. Finally, the formal Hamiltonian description of solution-state NMR will be described and applied to explain two related phenomena strong coupling ( leaning of multiplets) and TOCSY mixing (the isotropic mixing sequence). 

You may have noticed that the two multiplets in the upheld part of the ethylbenzene spectrum are not quite symmetrical. In general, a multiplet leans upward toward the signal of the protons responsible for the splitting. In the ethyl signal (Figure 13-25) the quartet at lower field leans toward the triplet at a higher field, and vice versa. 

Leaning of a multiplet. A multiplet often leans upward toward the protons that are causing the splitting. The ethyl multiplets in ethylbenzene lean toward each other. 

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