Magnetic Field Dependence of Electron Transfer and the Role of Electron Spin in Heme Enzymes: Horseradish Peroxidase

摘要

This observation has profound implications for the role of electron spin in all reactions that involve paramagnetic metal ions. When a diamagnetic substrate donates an electron to an S=1 paramagnetic acceptor, total electron spin will be con- served and reverse electron transfer will be limited to the triplet spin state. Intersystem crossing to the singlet spin state creates a species that is unreactive toward reverse electron transfer.