On the verification of different approaches describing spin-selective radical recombination

Bagryansky, V. A.; Borovkov, V. I.; Molin, Yu. N.

doi:10.1016/j.cplett.2013.03.047

Cited by 11 publications

(11 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…22,24 Experiments to probe the form ofK have been suggested but not yet performed. 17,28 In this report we describe what appears to be the first attempt to discriminate experimentally between the Haberkorn and Jones operators. We have used EPR (electron paramagnetic resonance) spectroscopy of the biradical form of a carotenoid-porphyrin-fullerene (CPF) triad molecule to measure the rates of its spin-selective recombination and the associated loss of singlet-triplet coherence.…”

Section: Introductionmentioning

confidence: 99%

Spin-selective recombination reactions of radical pairs: Experimental test of validity of reaction operators

Maeda

Liddell

Gust

et al. 2013

The Journal of Chemical Physics

View full text Add to dashboard Cite

Spin-selective reactions of radical pairs are conventionally modelled using an approach that dates back to the 1970s [R. Haberkorn, Mol. Phys. 32, 1491 (1976)]. An alternative approach based on the theory of quantum measurements has recently been suggested [J. A. Jones and P. J. Hore, Chem. Phys. Lett. 488, 90 (2010)]. We present here the first experimental attempt to discriminate between the two models. Pulsed electron paramagnetic resonance spectroscopy has been used to investigate intramolecular electron transfer in the radical pair form of a carotenoid-porphyrin-fullerene molecular triad. The rate of spin-spin relaxation of the fullerene radical in the triad was found to be inconsistent with the quantum measurement description of the spin-selective kinetics, and in accord with the conventional model when combined with spin-dephasing caused by rotational modulation of the anisotropic g-tensor of the fullerene radical.

show abstract

Section: Introductionmentioning

confidence: 99%

Spin-selective recombination reactions of radical pairs: Experimental test of validity of reaction operators

Maeda

Liddell

Gust

et al. 2013

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…In contrast, another experiment [26,27] reported evi-dence of a non-trivial state evolution of non-recombining radical-pairs, the rate of which appears to be consistent with the Jones-Hore prediction. A global and more detailed analysis of these two conflicting experiments will be undertaken elsewhere.…”

Section: Heisenberg's Cutmentioning

confidence: 66%

“…Returning to the chronological exposition, the first paper [8] illuminating the quantum-information substratum of RPM led to a resurgent interest of the spin chemistry community on the foundational aspects of the field [21][22][23][24][25][26][27][28][29][30], and in parallel to a flurry of activity in the quantum science community , even prompting some authors to announce, more or less timely, "the dawn of quantum biology" [58]. The main motivation and excitement behind this work has largely been RPM's relation to the avian magnetic compass.…”

Section: Introductionmentioning

confidence: 99%

The radical-pair mechanism as a paradigm for the emerging science of quantum biology

Kominis

2015

Mod. Phys. Lett. B

View full text Add to dashboard Cite

The radical-pair mechanism was introduced in the 1960's to explain anomalously large EPR and NMR signals in chemical reactions of organic molecules. It has evolved to the cornerstone of spin chemistry, the study of the effect electron and nuclear spins have on chemical reactions, with the avian magnetic compass mechanism and the photosynthetic reaction center dynamics being prominent biophysical manifestations of such effects. In recent years the radical-pair mechanism was shown to be an ideal biological system where the conceptual tools of quantum information science can be fruitfully applied. We will here review recent work making the case that the radicalpair mechanism is indeed a major driving force of the emerging field of quantum biology. * i → S D •+ A •− driven

show abstract

“…The pronounced effect of the ST-dephasing is in line with a previous suggestion to use radical triads to experimentally discriminate the Haberkorn and Jones-Hore approaches to spin-selective recombination. 40 However, only for the n = 4 system, this is reflected in the steady-state yield.…”

Section: The Journal Of Chemical Physicsmentioning

confidence: 99%

F-cluster: Reaction-induced spin correlation in multi-radical systems

Kattnig

2021

The Journal of Chemical Physics

View full text Add to dashboard Cite

We provide a theoretical analysis of spin-selective recombination processes in clusters of n ≥ 3 radicals. Specifically, we discuss how spin correlation can ensue from random encounters of n radicals, i.e., "F-clusters" as a generalization of radical F-pairs, acting as precursors of spin-driven magnetic field effects. Survival probabilities and the spin correlation of the surviving radical population, as well as transients, are evaluated by expanding the spin density operator in an operator basis that is closed under application of the Haberkorn recombination operator and singlet-triplet dephasing. For the primary spin cluster, the steady-state density operator is found to be independent of the details of the recombination network, provided that it is irreducible; pairs of surviving radicals are triplet-polarized independent of whether they are actually reacting with each other. The steady state is independent of the singlet-triplet dephasing, but the kinetics and the population of sister clusters of smaller size can depend on the degree of dephasing. We also analyze reaction-induced singlet-triplet interconversion in radical pairs due to radical scavenging by initially uncorrelated radicals ("chemical Zeno effect"). We generalize previous treatments for radical triads by discussing the effect of spin-selective recombination in the original pair and extending the analysis to four radicals, i.e., radical pairs interacting with two radical scavengers.

show abstract

On the verification of different approaches describing spin-selective radical recombination

Cited by 11 publications

References 25 publications

Spin-selective recombination reactions of radical pairs: Experimental test of validity of reaction operators

Spin-selective recombination reactions of radical pairs: Experimental test of validity of reaction operators

The radical-pair mechanism as a paradigm for the emerging science of quantum biology

F-cluster: Reaction-induced spin correlation in multi-radical systems

Contact Info

Product

Resources

About