title: General magnetic transition dipole moments for electron paramagnetic resonance.
abstract: We present general expressions for the magnetic transition rates in electron paramagnetic resonance (EPR) experiments of anisotropic spin systems in the solid state. The expressions apply to general spin centers and arbitrary excitation geometry (Voigt, Faraday, and intermediate). They work for linear and circular polarized as well as unpolarized excitation, and for crystals and powders. The expressions are based on the concept of the (complex) magnetic transition dipole moment vector. Using the new theory, we determine the parities of ground and excited spin states of high-spin (S=5/2) Fe(III) in hemin from the polarization dependence of experimental EPR line intensities.
authors.affiliation: Berlin Joint EPR Laboratory, Institut für Silizium-Photovoltaik, Helmholtz-Zentrum Berlin für Materialien und Energie, D-12489 Berlin, Germany.
authors.forename: Joscha
authors.initials: J
authors.lastname: Nehrkorn
authors.affiliation: Berlin Joint EPR Laboratory, Institut für Silizium-Photovoltaik, Helmholtz-Zentrum Berlin für Materialien und Energie, D-12489 Berlin, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Schnegg
authors.affiliation: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, D-12489 Berlin, Germany.
authors.forename: Karsten
authors.initials: K
authors.lastname: Holldack
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Stoll
mesh_terms: D016880:Anisotropy; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D006427:Hemin / Q000737:chemistry; D060328:Magnetic Phenomena; D008962:Models, Theoretical
chemical_list: D006427:Hemin