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Heisenberg Dimer Single Molecule Magnets in a Strong Magnetic Field

Dmitri V. Efremov·Richard A. Klemm
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Abstract

We calculate the static and dynamic properties of single crystal, single molecule magnets consisting of equal spin $S=1/2$ or 5/2 dimers. The spins in each dimer interact with each other via the Heisenberg exchange interaction and with the magnetic induction ${\bf B}$ via the Zeeman interaction, and interdimer interactions are negligible. For antiferromagnetic couplings, the static magnetization and specific heat exhibit interesting low temperature $T$ and strong ${\bf B}$ quantum effects. We calculate the frequency spectrum of the Fourier transform of the real part of the time autocorrelation function ${\cal C}_{11}(t)$ for arbitrary $T, {\bf B}$, and compare our results with those obtained for classical spins. We also calculate the inelastic neutron magnetic dynamical structure factor $S({\bf q},ω)$ at arbitrary $T, {\bf B}$.

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BibTeXRIS

Dmitri V. Efremov, Richard A. Klemm. 2002-10-05. Heisenberg Dimer Single Molecule Magnets in a Strong Magnetic Field. https://doi.org/10.1103/physrevb.66.174427

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