Inelastic tunneling through magnetically anisotropic molecules is studiedtheoretically in the presence of a strong magnetic field. Since the molecularorientation is not well controlled in tunneling experiments, we considerarbitrary angles between easy axis and field. This destroys all conservationlaws except that of charge, leading to a rich fine structure in thedifferential conductance. Besides single molecules we also study monolayers ofmolecules with either aligned or random easy axes. We show that detailedinformation on the molecular transitions and orientations can be obtained fromthe differential conductance for varying magnetic field. For random easy axes,averaging over orientations leads to van Hove singularities in the differentialconductance. Rate equations in the sequential-tunneling approximation areemployed. An efficient approximation for their solution for complex moleculesis presented. The results are applied to Mn12-based magnetic molecules.
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