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Mechanism of Ground State Selection in the Frustrated Molecular Spin Cluster V15

G. Chaboussant·S. T. Ochsenbein·A. Sieber·H. -U. Guedel·H. Mutka·A. Mueller·B. Barbara
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Abstract

We report an inelastic neutron scattering (INS) study under a magnetic field on the frustrated molecular spin cluster $V_{15}$. Several field-dependent transitions are observed and provide a comprehensive understanding of the low-energy quantum spin states. The energy gap $2 Δ_{0}\approx 27(3)μ$eV between the two lowest $S=1/2$ Kramers doublets is unambiguously attributed to a symmetry lowering of the cluster. The INS data are mapped onto an S=1/2 Antiferromagnetic Heisenberg triangle with scalene distortion. A quantitative description of the wavefunction mixing within the ground state is derived.

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G. Chaboussant, S. T. Ochsenbein, A. Sieber, H. -U. Guedel, H. Mutka, A. Mueller, B. Barbara. 2004-01-29. Mechanism of Ground State Selection in the Frustrated Molecular Spin Cluster V15. https://doi.org/10.1209/epl%2Fi2004-10008-x

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