=== Nuclear Spin States of H2 ===Each hydrogen molecule (H2) consists of two hydrogen atoms linked by a covalent bond. If we neglect the small proportion of deuterium and tritium which are present, each hydrogen atom consists of one proton and one electron. The proton has an associated magnetic moment, which's associated with the proton's spin. In the H2 molecule, the spins of the two hydrogen nuclei (protons) couple to form a triplet state (I = 1, α1α2, (α1β2 + β1α… (More on Parahydrogen)