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Quantum Phase Interference and Neel-Vector Tunneling in Antiferromagnetic Molecular Wheels

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 نشر من قبل Oliver Waldmann
 تاريخ النشر 2009
  مجال البحث فيزياء
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The antiferromagnetic molecular wheel Fe18 of eighteen exchange-coupled Fe(III) ions has been studied by measurements of the magnetic torque, the magnetization, and the inelastic neutron scattering spectra. The combined data show that the low-temperature magnetism of Fe18 is very accurately described by the Neel-vector tunneling (NVT) scenario, as unfolded by semiclassical theory. In addition, the magnetic torque as a function of applied field exhibits oscillations that reflect the oscillations in the NVT tunnel splitting with field due to quantum phase interference.



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