Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation
Radical pair recombination reactions are normally described using a quantum mechanical master equation for the electronic and nuclear spin density operator. The electron spin state selective (singlet and triplet) recombination processes are described with a Haberkorn reaction term in this master equ...
| Κύριοι συγγραφείς: | , , |
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| Μορφή: | Journal article |
| Γλώσσα: | English |
| Έκδοση: |
AIP Publishing
2018
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| _version_ | 1826292061569024000 |
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| author | Fay, T Lindoy, L Manolopoulos, D |
| author_facet | Fay, T Lindoy, L Manolopoulos, D |
| author_sort | Fay, T |
| collection | OXFORD |
| description | Radical pair recombination reactions are normally described using a quantum mechanical master equation for the electronic and nuclear spin density operator. The electron spin state selective (singlet and triplet) recombination processes are described with a Haberkorn reaction term in this master equation. Here we consider a general spin state selective electron transfer reaction of a radical pair and use Nakajima-Zwanzig theory to derive the master equation for the spin density operator, thereby elucidating the relationship between non-adiabatic reaction rate theory and the Haberkorn reaction term. A second order perturbation theory treatment of the diabatic coupling naturally results in the Haberkorn master equation with an additional reactive scalar electron spin coupling term. This term has been neglected in previous spin chemistry calculations, but we show that it will often be quite significant. We also show that beyond the second order in perturbation theory, i.e., beyond the Fermi golden rule limit, an additional reactive singlet-triplet dephasing term appears in the master equation. A closed form expression for the reactive scalar electron spin coupling in terms of the Marcus theory parameters that determine the singlet and triplet recombination rates is presented. By performing simulations of radical pair reactions with the exact hierarchical equations of motion method, we demonstrate that our master equations provide a very accurate description of radical pairs undergoing spin-selective non-adiabatic electron transfer reactions. The existence of a reactive electron spin coupling may well have implications for biologically relevant radical pair reactions such as those which have been suggested to play a role in avian magnetoreception. |
| first_indexed | 2024-03-07T03:08:54Z |
| format | Journal article |
| id | oxford-uuid:b37df1d2-e7d6-4e24-b3b4-094edb65c18d |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T03:08:54Z |
| publishDate | 2018 |
| publisher | AIP Publishing |
| record_format | dspace |
| spelling | oxford-uuid:b37df1d2-e7d6-4e24-b3b4-094edb65c18d2022-03-27T04:19:35ZSpin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equationJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:b37df1d2-e7d6-4e24-b3b4-094edb65c18dEnglishSymplectic Elements at OxfordAIP Publishing2018Fay, TLindoy, LManolopoulos, DRadical pair recombination reactions are normally described using a quantum mechanical master equation for the electronic and nuclear spin density operator. The electron spin state selective (singlet and triplet) recombination processes are described with a Haberkorn reaction term in this master equation. Here we consider a general spin state selective electron transfer reaction of a radical pair and use Nakajima-Zwanzig theory to derive the master equation for the spin density operator, thereby elucidating the relationship between non-adiabatic reaction rate theory and the Haberkorn reaction term. A second order perturbation theory treatment of the diabatic coupling naturally results in the Haberkorn master equation with an additional reactive scalar electron spin coupling term. This term has been neglected in previous spin chemistry calculations, but we show that it will often be quite significant. We also show that beyond the second order in perturbation theory, i.e., beyond the Fermi golden rule limit, an additional reactive singlet-triplet dephasing term appears in the master equation. A closed form expression for the reactive scalar electron spin coupling in terms of the Marcus theory parameters that determine the singlet and triplet recombination rates is presented. By performing simulations of radical pair reactions with the exact hierarchical equations of motion method, we demonstrate that our master equations provide a very accurate description of radical pairs undergoing spin-selective non-adiabatic electron transfer reactions. The existence of a reactive electron spin coupling may well have implications for biologically relevant radical pair reactions such as those which have been suggested to play a role in avian magnetoreception. |
| spellingShingle | Fay, T Lindoy, L Manolopoulos, D Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation |
| title | Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation |
| title_full | Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation |
| title_fullStr | Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation |
| title_full_unstemmed | Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation |
| title_short | Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation |
| title_sort | spin selective electron transfer reactions of radical pairs beyond the haberkorn master equation |
| work_keys_str_mv | AT fayt spinselectiveelectrontransferreactionsofradicalpairsbeyondthehaberkornmasterequation AT lindoyl spinselectiveelectrontransferreactionsofradicalpairsbeyondthehaberkornmasterequation AT manolopoulosd spinselectiveelectrontransferreactionsofradicalpairsbeyondthehaberkornmasterequation |