Rotating-frame nuclear magnetic resonance study of the superprotonic conduction in LiH2PO4

The proton and phosphorus dynamics of the superprotonic conduction in the LiH2PO4 system has been studied by means of 1H and 31P NMR rotating-frame nuclear magnetic resonance (NMR). The temperature-dependent 1H NMR rotating-frame spin–lattice relaxation time measurements revealed in a sensitive manner the evolution of the microscopic environment and proton dynamics of the two distinct hydrogen-bond types in the system, which is quite compatible with the electrical conductivity and the impedance spectroscopy measurements. Besides, the proton dynamics was found to be coupled to the reorientational motion of the PO4 tetrahedra.