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Definitive spectroscopic determination of the transverse interactions responsible for the magnetic quantum tunneling in Mn12-acetate

S. Hill·R. S. Edwards·S. I. Jones·J. M. North·N. S. Dalal
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Abstract

We present detailed angle-dependent single crystal electron paramagnetic resonance (EPR) data for field rotations in the hard plane of the S=10 single molecule magnet Mn12-acetate. A clear four-fold variation in the resonance positions may be attributed to an intrinsic fourth order transverse anisotropy (O44). Meanwhile, a four-fold variation of the EPR lineshapes confirms a recently proposed model wherein disorder associated with the acetic acid of crystallization induces a locally varying quadratic (rhombic) transverse anisotropy (O22). These findings explain most aspects of the magnetic quantum tunneling observed in Mn12-acetate.

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S. Hill, R. S. Edwards, S. I. Jones, J. M. North, N. S. Dalal. 2003-04-10. Definitive spectroscopic determination of the transverse interactions responsible for the magnetic quantum tunneling in Mn12-acetate. https://doi.org/10.1103/physrevlett.90.217204

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