Spin selectivity in electron transfer in photosystem i

Itai Carmeli, Karuppannan Senthil Kumar, Omri Heifler, Chanoch Carmeli, Ron Naaman*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

82 Scopus citations

Abstract

Photosystem I (PSI) is one of the most studied electron transfer (ET) systems in nature; it is found in plants, algae, and bacteria. The effect of the system structure and its electronic properties on the electron transfer rate and yield was investigated for years in details. In this work we show that not only those system properties affect the ET efficiency, but also the electrons' spin. Using a newly developed spintronic device and a technique which enables control over the orientation of the PSI monolayer relative to the device (silver) surface, it was possible to evaluate the degree and direction of the spin polarization in ET in PSI. We find high-spin selectivity throughout the entire ET path and establish that the spins of the electrons being transferred are aligned parallel to their momenta. The spin selectivity peaks at 300 K and vanishes at temperatures below about 150 K. A mechanism is suggested in which the chiral structure of the protein complex plays an important role in determining the high-spin selectivity and its temperature dependence. Our observation of high light induced spin dependent ET in PSI introduces the possibility that spin may play an important role in ET in biology.

Original languageEnglish
Pages (from-to)8953-8958
Number of pages6
JournalAngewandte Chemie - International Edition
Volume53
Issue number34
DOIs
StatePublished - 18 Aug 2014

Funding

FundersFunder number
European Research Council

    Keywords

    • chirality
    • electron transfer
    • photosystem I
    • temperature-dependent charge transfer

    Fingerprint

    Dive into the research topics of 'Spin selectivity in electron transfer in photosystem i'. Together they form a unique fingerprint.

    Cite this