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Incommensurate Transverse Anisotropy Induced by Disorder and Spin-Orbit-Vibron Coupling in Mn12-acetate

Kyungwha Park·Mark R. Pederson·Tunna Baruah·Noam Bernstein·Jens Kortus·Steven L. Richardson·Enrique del Barco·Andrew D. Kent·Steve Hill·Naresh S. Dalal
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Abstract

It has been shown within density-functional theory that in Mn$_{12}$-acetate there are effects due to disorder by solvent molecules and a coupling between vibrational and electronic degrees of freedom. We calculate the in-plane principal axes of the second-order anisotropy caused by the second effect and compare them with those of the fourth-order anisotropy due to the first effect. We find that the two types of the principal axes are not commensurate with each other, which results in a complete quenching of the tunnel-splitting oscillation as a function of an applied transverse field.

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Kyungwha Park, Mark R. Pederson, Tunna Baruah, Noam Bernstein, Jens Kortus, Steven L. Richardson, Enrique del Barco, Andrew D. Kent, Steve Hill, Naresh S. Dalal. 2004-09-08. Incommensurate Transverse Anisotropy Induced by Disorder and Spin-Orbit-Vibron Coupling in Mn12-acetate. https://doi.org/10.1063/1.1847851

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