Polarization-transfer electron-Zeeman resolved EPR

Polarization-transfer electron-Zeeman resolved (EZ) EPR is introduced. In this two-dimensional pulse EPR method, which is based on the stimulated-echo sequence, the magnetic field is changed during the pulse sequence by applying a sinusoidal field of variable amplitude. EZ–EPR can be used to improve the spectral resolution of disordered systems with g anisotropy or to separate overlapping spectra of sites with different g values in single-crystal EPR studies. A theoretical description of the method is given, and model calculations as well as experiments on disordered systems with anisotropic electron Zeeman interactions are presented.