Abstract
We report on the direct observation of the intrinsic magnetization behavior of Mackay icosahedral Au nanoparticles. The spin arrangements in 3.5-nm icosahedral Au particles are found to be ferrimagnetic-like, where the core and surface moments point in opposite directions, with a net spontaneous magnetic moment of 16 μB per particle. The unpaired spins behave as J = 1/2 quantum spins. The average level separation is found to be a factor of ~1.53 larger than that estimated according to the Kubo formula for spherical Au particles. This reflects the fact that there are considerably fewer atoms packed in a particle with an icosahedral geometry than with a spherical one.
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This research was supported by grants from the National Science Council of Taiwan, under Grant Nos. NSC 95-2112-M-008-039-MY3 and NSC 96-2112-M-259-008.
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Wu, CM., Li, CY., Kuo, YT. et al. Quantum spins in Mackay icosahedral gold nanoparticles. J Nanopart Res 12, 177–185 (2010). https://doi.org/10.1007/s11051-009-9592-3
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DOI: https://doi.org/10.1007/s11051-009-9592-3