Theory of the conductivity of the pinned Fröhlich charge density wave

Recent microscopic calculations that use the concept of the Fr\"ohlich charge-density-wave (CDW) conductivity in the region of a mean-field Peierls transition cannot be applied to discuss the conductivity in K₂Pt(CN)₄{Br}0.3·3{H}₂$O (KCP). An approximate formula for the low-temperature CDW conductivity can be derived on the basis of a phenomenological model for the pinning of a CDW. We find that this CDW conductivity contributes only a small fraction to the measured conductivity at low temperatures. Only close to the pinning temperature Tₚ~150^∘K could this contribution be significant.