Chirality-Induced Spin Selectivity (CISS) in Electron Donor-Bridge-Acceptor Systems

Michael R. Wasielewski

Department of Chemistry
Northwestern University
Evanston, IL 60208-3113

Electron transmission through chiral molecules and materials attached to conductive surfaces has been shown to result in spin filtering to produce highly spin-polarized electrons. This effect is termed Chirality-Induced Spin Selectivity (CISS). While chiral molecules break parity symmetry, they retain time-reversal symmetry. Thus, it is necessary to have a charge flowing through them in order to break time-reversal symmetry and thus meet the symmetry requirements for generating a magnetic field along the charge’s velocity direction. Until now, this effect has not been demonstrated in molecular electron donor-chiral bridge-acceptor (D-B^c-A) systems. Given that chiral molecules are ubiquitous in both chemical and biological electron transfer reactions, ascertaining the effect of CISS on the electron transfer and spin dynamics of these systems is important. In addition, CISS provides a potential means of controlling spin dynamics that has applications in quantum information science. In this presentation we will describe our studies of the CISS effect on the spin dynamics of electron transfer reactions in small molecule D-B^c-A systems as well as in synthetic DNA hairpins.

This abstract is for the Florida Award Symposium on June 2 2023 at 1:30-6:00 pm.