Some Peculiarities of Proton Transport in Quasi-One-Dimensional Hydrogen-Bonded Chains

TL;DR

This paper theoretically investigates proton transport in hydrogen-bonded chains, revealing a transition from insulator to metal-like behavior influenced by phonon interactions and Grotthuss mechanism, with detailed analysis of conductivity frequency dependencies.

Contribution

It introduces a two-stage transport model considering optical phonon interactions and analyzes the insulator-metal transition and frequency-dependent conductivity peculiarities.

Findings

Transition from insulator to metal-like state with temperature

Influence of Grotthuss mechanism on transition character

Distinct frequency dependencies of conductivity parts

Abstract

The protonic conductivity in the hydrogen bonded chains is investigated theoretically in the framework of the two-stage transport model. The strong interactions with optical phonon stretching mode are considered. We obtain the transition from the insulator to the metal-type state from the temperature dependencies of the hopping conductivity and analyze the influence of the specific Grotthuss mechanism on the transition character. We investigate also the main peculiarities in the frequency dependencies of the band and hopping conductivity parts which appear due to above-mentioned two-stage process of the proton migration along the chain.