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arXiv · 0911.2810

Rotational States of Magnetic Molecules

E. M. Chudnovsky·D. A. Garanin
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Abstract

We study a magnetic molecule that exhibits spin tunneling and is free to rotate about its anisotropy axis. Exact low-energy eigenstates of the molecule that are superpositions of spin and rotational states are obtained. We show that parameter $\alpha = 2(\hbar S)^2/(I\Delta)$ determines the ground state of the molecule. Here $\hbar S$ is the spin, $I$ is the moment of inertia, and $\Delta$ is the tunnel splitting. The magnetic moment of the molecule is zero at $\alpha < \alpha_c = [1-1/(2S)^{2}]^{-1}$ and non-zero at $\alpha > \alpha_c$. At $\alpha \to \infty$ the spin of the molecule localizes in one of the directions along the anisotropy axis.

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E. M. Chudnovsky, D. A. Garanin. 2009-11-14. Rotational States of Magnetic Molecules. https://doi.org/10.1103/physrevb.81.214423

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