SINGLE-CRYSTAL EPR OF MN-12-ACETATE CLUSTERS

We have used electron paramagnetic resonance (EPR) to study the energy level diagram of the Mn-12-cluster compound, in the frequency range f rom 35 to 115 GHz. Our high sensitivity allows the observation of mult iple resonances, and their temperature dependence, on high-quality sin gle crystals. The results are in qualitative agreement with the pictur e of a strong axial anisotropy. Measurements with the field applied pa rallel and perpendicular to the easy axis reveal significant zero-fiel d splittings and level crossings, as predicted theoretically. (C) 1998 Elsevier Science B.V. All rights reserved.