Biradical spin dynamics with distance-dependent exchange interaction and electron transfer efficiency

doi:10.1016/0009-2614(90)85289-O

Chemical Physics Letters

Volume 173, Issue 4, 12 October 1990, Pages 387-392

https://doi.org/10.1016/0009-2614(90)85289-O Get rights and content

Abstract

The spin dynamics and reaction kinetics of photogenerated zwitterionic biradicals of the type ²A⁻(CH₂)_n²D⁺ (n = 8, 9, 10) are described for a model which assumes the same AD distance dependence for a “through space” exchange interaction and for the efficiency of electron back-transfer to the singlet ground state ¹A(CH₂)_n¹D and to a triplet excited state ³A*(CH₂)_n¹D. The model is independent of the length n of the polymethylene chain and accounts well for the three type of observation on the biradicals: the mono-exponential character of the biradical decay, the life time associated with this decay, and the magnetic field dependence of the yield of the triplet excited state.

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¹: New address: Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-7000 Stuttgart, Federal Republic of Germany.

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Biradical spin dynamics with distance-dependent exchange interaction and electron transfer efficiency

Abstract

Chem. Phys. Letters

Chem. Phys. Letters

Science

Faraday Discussions Chem. Soc.

J. Chem. Phys.