Multiple Quantum NMR in One-Dimensional and Nano-Scale Systems: Theory and Computer Simulations

We investigate several exactly solvable models of multiple quantum (MQ) NMR dynamics. We study MQ NMR dynamics of one-dimensional systems (chains and rings) and nano-voids filled with spin-carrying atoms or molecules in a strong external magnetic field. Our focus is the problem of the profile of MQ NMR coherences (i.e., the dependence of the intensities of MQ NMR coherences on their orders). We find that integrable one-dimensional systems exhibit peculiar behavior that does not shed much light on a more generic situation. On the other hand, important lessons can be extracted from our solution for the nano-scale systems. We find that the profile of the intensities of the MQ NMR coherences is rather exponential than Gaussian as was proposed earlier. We also address the cluster growth in the course of the evolution of MQ NMR coherences.