Quantum Mechanics

  • Alan LewisEmail author
Part of the Springer Theses book series (Springer Theses)


In this chapter, we shall outline the quantum mechanical description of the spin dynamics of a radical pair reaction. To begin, we will sketch the origin of the Hamiltonian which governs the evolution of the electron and nuclear spins in a radical pair. We will then describe the Haberkorn operator used to account for the recombination of radical pairs, and introduce the ensemble dynamics of the radical pair, which provide a connection to experimental measurements. Using this machinery, we shall demonstrate an efficient method of calculating these ensemble averages and discuss its limitations, which motivate the development of approximate semiclassical theories of spin dynamics in Chap.  3. We will then introduce spin correlation tensors, which may be used in the special case where there is no coupling between electron spins to further reduce the computational time required to simulate radical pair reactions. Finally, we shall discuss relaxation effects, noting that the difficulty of including them in fully quantum mechanical simulations provides additional motivation to find semiclassical models which can account for these effects.


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.The James Franck InstituteUniversity of ChicagoChicagoUSA

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