Long-range electron transport mediated by solitons in Donor–Alpha-Helix–Acceptor systems

Abstract

It is knownthatDavydovsolitons[1]provide the long-range electron transport in an isolated one-dimensional molecular chain. Such a soliton is a bound state of a quasiparticle and local deformation of the chain formed due to the electron-lattice interaction. Here the results are reported on the study of the long-range electron and energy transfer mediated by solitons formed in an alpha-helical three-spine polypeptide coupled to donor and acceptor molecules at opposite ends [2]. It is shown that there exists the broad interval of the parameters for which an electron initially located on the donor, tunnels onto the chain where it forms a solitoocated on the donor, tunnels onto the chain where it forms a soliton-like state, which then travels to the opposite end, where it is captured by the acceptor. It is shown that the e÷ciency of the electron transport from the donor to the acceptor can reach 90%. These results explain highly e÷cient long-range donor-accepor electron transport in redox reactions in photosynthesis and cellular respiration in biological systems, and in donor-acceptor systems mediated by various types of long molecular chains, widely used in modern microelectronics and nanotechnologies [3].