Journal of Nanoparticle Research

, Volume 12, Issue 1, pp 177–185 | Cite as

Quantum spins in Mackay icosahedral gold nanoparticles

  • Chun-Ming Wu
  • Chi-Yen Li
  • Yen-Ting Kuo
  • Chin-Wei Wang
  • Sheng-Yun Wu
  • Wen-Hsien Li
Research Paper

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.

Keywords

Au nanoparticles Quantum spin Synthesis Ferrimagnetism 

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Chun-Ming Wu
    • 1
  • Chi-Yen Li
    • 1
  • Yen-Ting Kuo
    • 1
  • Chin-Wei Wang
    • 1
  • Sheng-Yun Wu
    • 2
  • Wen-Hsien Li
    • 1
  1. 1.Department of PhysicsNational Central UniversityJhongliTaiwan
  2. 2.Department of PhysicsNational Dong Hwa UniversityHualienTaiwan

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