High Field Electron Paramagnetic Resonance (HFEPR) study on a Mn(IV) monomer

In this work we investigated the magnetic anisotropy of a Mn (IV) monomer via axial and rhombic zero field splitting terms $D, E$. The d$^{3}$ ion sits in an octahedral environment in a P 21/c space group. The complex is studied via single crystal and powder HFEPR over a wide range of frequencies 49GHz to 416GHz and temperatures 2 to 60K. The angle dependence at low temperature and frequency ($\sim$88GHz) reveals a minimum of the resonance field, when the long axis of the crystal is along the magnetic field. The same behavior is observed at higher frequency ($\sim$240GHz). Furthermore, pulse EPR experiments in high frequency quasi-optical spectrometer at low temperature ($\sim$1.487K) a spin echo could be observed and we were able to observe the variation of the T$_{2}$ times as a function of the magnetic field orientation, and as a function of the temperature.