The radical pair mechanism and the avian chemical compass: Quantum coherence and entanglement

Yiteng Zhang, Gennady P. Berman, Sabre Kais

Research output: Contribution to journalArticle

10 Citations (Scopus)


We review the spin radical pair mechanism which is a promising explanation of avian navigation. This mechanism is based on the dependence of product yields on (1) the hyperfine interaction involving electron spins and neighboring nuclear spins and (2) the intensity and orientation of the geomagnetic field. This review describes the general scheme of chemical reactions involving radical pairs generated from singlet and triplet precursors; the spin dynamics of the radical pairs; and the magnetic field dependence of product yields caused by the radical pair mechanism. The main part of the review includes a description of the chemical compass in birds. We review: the general properties of the avian compass; the basic scheme of the radical pair mechanism; the reaction kinetics in cryptochrome; quantum coherence and entanglement in the avian compass; and the effects of noise. We believe that the quantum avian compass can play an important role in avian navigation and can also provide the foundation for a new generation of sensitive and selective magnetic-sensing nano-devices.

Original languageEnglish
Pages (from-to)1327-1341
Number of pages15
JournalInternational Journal of Quantum Chemistry
Issue number19
Publication statusPublished - 1 Oct 2015



  • chemical compass
  • quantum coherence
  • quantum entanglement

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Atomic and Molecular Physics, and Optics
  • Physical and Theoretical Chemistry

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