Multiple nearest-neighbor exchange model for the frustrated magnetic molecules Mo72Fe30 and Mo72Cr30

Abstract

Our measurements of the differential susceptibility dM/dH of the frustrated magnetic molecules Mo72Fe30 and Mo72Cr30 reveal a pronounced dependence on magnetic field (H) and temperature (T) in the low H - low T regime, contrary to the predictions of existing models. Excellent agreement with experiment is achieved upon formulating a nearest-neighbor classical Heisenberg model where the 60 nearest-neighbor exchange interactions in each molecule, rather than being identical as has been assumed heretofore, are described by a two-parameter probability distribution of values of the exchange constant. We suggest that the probability distribution provides a convenient phenomenological platform for summarizing the combined effects of multiple microscopic mechanisms that disrupt the idealized picture of a Heisenberg model based on a single value of the nearest-neighbor exchange constant.

8 pages, 5 figures

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Cited by in corpus (11)

• Properties of highly frustrated magnetic molecules studied by the finite-temperature Lanczos method
• High-Order Coupled Cluster Method Study of Frustrated and Unfrustrated Quantum Magnets in External Magnetic Fields
• Eighth-order high-temperature expansion for general Heisenberg Hamiltonians
• Accuracy of the finite-temperature Lanczos method compared to simple typicality-based estimates
• Large-scale numerical investigations of the antiferromagnetic Heisenberg icosidodecahedron
• Frustration effects in antiferromagnetic molecules: the cuboctahedron
• A correlator product state study of molecular magnetism in the giant Keplerate Mo72Fe30
• Influence of intermolecular interactions on magnetic observables
• Quantum Dynamics in Classical Spin Baths
• Thermal features of Heisenberg antiferromagnets on edge- versus corner-sharing triangular-based lattices: A message from spin waves
• Evidence of Low-Energy Singlet Excited States in the Spin-1/2 Polyhedral Clusters {Mo${}_{72}$V${}_{30}$} and {W${}_{72}$V${}_{30}$} with Strongly Frustrated Kagomé Networks