NMR, conductivity and neutron scattering investigation of ionic dynamics in the anhydrous polymer protonic conductor PEO(H3PO4)x)

Abstract

The temperature dependence of the conductivity is shown to be governed by the segmental chain motion. The frequency dependence of the phosphorus spin-lattice relaxation rate is interpreted using a stretched exponential correlation function exp[−(t/τ)β] with β=0.277. The long-range diffusion coefficient of the molecule (measured by the pulsed field gradient NMR technique) is shown to be quite close to the short-range diffusion coefficient of the chain segments determined from NQES.