Work

Effective spin Hamiltonians for the quantum-rotor tunneling problem in pulse EPR

Year: 2025

Type: article

Abstract: We analyzed the spin-tunneling Hamiltonian of a quantum rotor coupled to an electron spin. Even under conditions where the rotor's nuclei are magnetically inequivalent, the symmetry between the rotor's state exchange and relabeling of nuclei holds exactly; hence, the Hamiltonian can be simplified with the help of a group theoretical approach. We demonstrated this principle on methyl-type and methane-type rotors, both in protonated and deuterated forms. We showed that the spin-tunneling problem in these cases is equivalent to solving a few spin-only problems where the tunneling interaction appears in the form of an effective spin Hamiltonian. We derived spin-operator forms of the effective Hamiltonians and discussed the application to the two-pulse electron spin echo envelope modulation experiment.

Source: The Journal of Chemical Physics

DOI: 10.1063/5.0283582

Authors: S. Kuzin, G. Jeschke

Institution: ETH Zurich

Language: English

Topic: Electron Spin Resonance Studies

Subfield: Biophysics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Estimated APC paid: $3,500

Funder: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung