Proton NMR: Reading Chemical Shifts

Proton NMR chemical shifts show how hydrogen-1 nuclei behave in a sample. Organic molecules are mostly made of carbon and hydrogen, and hydrogen-1, or protium, is the most abundant hydrogen isotope used in NMR. Because it has a large gyromagnetic ratio, its spin states are separated by a relatively large energy gap. That gap...

Organic molecules primarily contain carbon and hydrogen atoms.

While all hydrogen isotopes are NMR-active, protium or hydrogen-1 is the most abundant and has a strong NMR absorption signal due to its large magnetogyric ratio, which causes significant energy separation between its spin states.

The absorption signals of all the proti...