Observation of a Distribution of Internal Transverse Magnetic Fields in a Mn12-Based Single Molecule Magnet

Abstract

A distribution of internal transverse magnetic fields has been observed in single molecule magnet (SMM) Mn12-BrAc in the pure magnetic quantum tunneling (MQT) regime. Magnetic relaxation experiments at 0.4 K are used to produce a hole in the distribution of transverse fields whose angle and depth depend on the orientation and amplitude of an applied transverse ``digging field.'' The presence of such transverse magnetic fields can explain the main features of resonant MQT in this material, including the tunneling rates, the form of the relaxation and the absence of tunneling selection rules. We propose a model in which the transverse fields originate from a distribution of tilts of the molecular magnetic easy axes.

arXiv comment4 pages

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Cited by in corpus (5)

• Determination of the magnetic anisotropy axes of single-molecule magnets
• Effect of extra electrons on the exchange and magnetic anisotropy in the anionic single-molecule magnet Mn12
• Evidence for the S=9 excited state in Mn12-bromoacetate measured by electron paramagnetic resonance
• Crystal lattice desolvation effects on the magnetic quantum tunneling of single-molecule magnets
• Collective electromagnetic relaxation in crystals of molecular magnets