Are the prefactor anomalies in superionic conductors due to 1-D effects?

We have examined both the ionic conductivity and the NMR line narrowing in two channel-structured superionic conductors in the light of Richards' one-dimensional theory. For Li₂Ti₃O₇ the ionic conductivity is not sufficiently anisotropic to explain the observed small NMR prefactor in terms of i-D effects. For β-LiAlSiO₄ the NMR line narrowing in the crossover region does not yield the predicted large change in the activation energy given by the 1-D theory.