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Updated: Jun 26, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Enhanced intersystem crossing in three-spin systems: a perturbation theory treatment
Sina Yeganeh1, Michael R Wasielewski, Mark A Ratner
1Department of Chemistry, Center for Nanofabrication and Molecular Self Assembly, Northwestern University, Evanston, Illinois 60208-3113, USA.
Abstract:
We present a simple model for analyzing the spin dynamics of a three-spin system representing a photoexcited chromophore coupled to a stable radical species. Perturbation theory yields a Fermi's Golden Rule-type rate expression that describes the formation of a local triplet on the chromophore through spin exchange with the radical. The error introduced by perturbation theory is evaluated for a number of parameters. Finally, we explore the effect of different energetic and coupling parameters on the rate of triplet formation and suggest how this model can be used to tune the enhanced intersystem crossing in three-spin systems.
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