Size dependence of ferromagnetism in gold nanoparticles: Mean field results

Fredrick Michael, Carlos Gonzalez, Vladimiro Mujica, Manuel Marquez, Mark A. Ratner

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

In this paper, a simple spin-spin Ising interaction model for the surface ferromagnetism is combined with the bulk Au diamagnetic response to model the size dependence of the magnetization of a Au nanoparticle. Using the maximum entropy formalism, we obtain the average temperature dependent magnetization within a mean field model. Our results qualitatively reproduce recent experimental observations of size-dependent magnetization of Au nanoparticles in which the ferromagnetic moment of thiol-capped nanoparticles is seen to increase for diameters larger than 0.7 nm, peaking at approximately 3 nm, and subsequently decreasing as the particle diameter increases further.

Original languageEnglish (US)
Article number224409
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume76
Issue number22
DOIs
StatePublished - Dec 12 2007
Externally publishedYes

Fingerprint

Ferromagnetism
Gold
ferromagnetism
Magnetization
gold
Nanoparticles
nanoparticles
magnetization
Sulfhydryl Compounds
thiols
Entropy
entropy
formalism
moments
interactions
Temperature
temperature

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Size dependence of ferromagnetism in gold nanoparticles : Mean field results. / Michael, Fredrick; Gonzalez, Carlos; Mujica, Vladimiro; Marquez, Manuel; Ratner, Mark A.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 76, No. 22, 224409, 12.12.2007.

Research output: Contribution to journalArticle

Michael, Fredrick ; Gonzalez, Carlos ; Mujica, Vladimiro ; Marquez, Manuel ; Ratner, Mark A. / Size dependence of ferromagnetism in gold nanoparticles : Mean field results. In: Physical Review B - Condensed Matter and Materials Physics. 2007 ; Vol. 76, No. 22.
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