Fig. 5: Scheme of the spin system simulated.
From: Nuclear spin polarization of lactic acid via exchange of parahydrogen-polarized protons
The system consisted of labile spins No. 1 and 2, a carbon spin No. 3, and a (firmly bound) proton spin No. 4 (left side). The spin system transitions between state X and Y happened with rate constants K1 = K2. The spins considered in the corresponding chemical system (right) are marked in red. A is a compound that generates labile protons (examples are given on the bottom of the right side). R1, R2, R3 and R4 are any rests.
