NMR "Pople Notation" HELP! All the examples in my textbook show molecules that have only three sets of multiplets (AX, AB, ABX, or AMX first oder spin systems). But what if I have a molecule with more than 3 spin systems, for example in 1-bromobutane: CH3-CH2-CH2-CH2-Br (there is a triplet, sextet, quintet, and triplet). Each proton is unique, i.e., no chemically equivalent shift H's, no magnetically equivalent protons, enantiotopic or diastereotopic protons. For this example, there is 4 spin systems, so do I have to describe it using 4 letters, but that seems impossible. I'm confused. So far, I think it is this (reading left to right of the molecule): A3 B2 B2 X2 Someone please explain to me Pople notation. Thank you.