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Many-Spin Effects and Tunneling Properties of Magnetic Molecules

M. Al-Saqer·V. V. Dobrovitski·B. N. Harmon·M. I. Katsnelson
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Abstract

Spin tunneling in molecular magnets has attracted much attention, however theoretical considerations of this phenomenon up to now have not taken into account the many-spin nature of molecular magnets. We present, to our knowledge, the first successful attempt of a realistic calculation of tunneling splittings for Mn$_{12}$ molecules, thus achieving a quantitatively accurate many-spin description of a real molecular magnet in the energy interval ranging from about 100 K down to 10$^{-12}$ K. Comparison with the results of the standard single-spin model shows that many-spin effects affect the tunneling splittings considerably. The values of ground state splitting given by single-spin and many-spin models differ from each other by a factor of five.

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M. Al-Saqer, V. V. Dobrovitski, B. N. Harmon, M. I. Katsnelson. 1999-09-18. Many-Spin Effects and Tunneling Properties of Magnetic Molecules. https://doi.org/10.1063/1.372675

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