English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Classical chemical kinetics use rate-equation models to describe how areaction proceeds in time. Such models are sufficient for describing statetransitions in a reaction where coherences between different states do notarise, or in other words, a reaction which contain only incoherent transitions.A prominent example reaction containing coherent transitions is theradical-pair model. The kinetics of such reactions is defined by the so-calledreaction operator which determines the radical-pair state as a function ofintermediate transition rates. We argue that the well-known concept of quantumwalks from quantum information theory is a natural and apt framework fordescribing multisite chemical reactions. By composing Kraus maps that act onlyon two sites at a time, we show how the quantum-walk formalism can be appliedto derive a reaction operator for the standard avian radical-pair reaction. Ourreaction operator predicts a recombination dephasing rate consistent withrecent experiments [J. Chem. Phys. {\bf 139}, 234309 (2013)], in contrast toprevious work by Jones and Hore [Chem. Phys. Lett. {\bf 488}, 90 (2010)]. Thestandard radical-pair reaction has conventionally been described by either anormalised density operator incorporating both the radical pair and reactionproducts, or by a trace-decreasing density operator that considers only theradical pair. We demonstrate a density operator that is both normalised andrefers only to radical-pair states. Generalisations to include additionaldephasing processes and an arbitrary number of sites are also discussed.

Coherent chemical kinetics as quantum walks I: Reaction operators for radical pairs