Directed polaron propagation in linear polypeptides induced by intramolecular vibrations and external electric pulses

TL;DR

This study models how polarons in alpha-helix polypeptides move in response to electric pulses, revealing significant displacement before delocalization, with implications for biophysical charge transport.

Contribution

It introduces a non-adiabatic model of polaron dynamics in polypeptides under electric pulses, highlighting a novel mechanism of charge propagation at physiological temperatures.

Findings

Polaron displacement of hundreds of lattice sites.

Electric pulses induce significant charge movement.

Implications for biophysical charge transport mechanisms.

Abstract

We study the propagation of $\alpha$-helix polarons in a model describing the non-adiabatic interaction between an electron and a lattice of quantum mechanical oscillators at physiological temperature. We show that when excited by a sub-picosecond electric pulse, as induced by experimentally observed sub-picosecond charge separation, the polaron is displaced by up to hundreds of lattice sites before the electron becomes delocalised. We discuss biophysical implications of our results.