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

44 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
Article number224409
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume76
Issue number22
DOIs
Publication statusPublished - Dec 12 2007

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

@article{480ca7d5d21d40f9801d091df59132f9,
title = "Size dependence of ferromagnetism in gold nanoparticles: Mean field results",
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.",
author = "Fredrick Michael and Carlos Gonzalez and Vladimiro Mujica and Manuel Marquez and Ratner, {Mark A}",
year = "2007",
month = "12",
day = "12",
doi = "10.1103/PhysRevB.76.224409",
language = "English",
volume = "76",
journal = "Physical Review B-Condensed Matter",
issn = "1098-0121",
publisher = "American Physical Society",
number = "22",

}

TY - JOUR

T1 - Size dependence of ferromagnetism in gold nanoparticles

T2 - Mean field results

AU - Michael, Fredrick

AU - Gonzalez, Carlos

AU - Mujica, Vladimiro

AU - Marquez, Manuel

AU - Ratner, Mark A

PY - 2007/12/12

Y1 - 2007/12/12

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=37249029920&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=37249029920&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.76.224409

DO - 10.1103/PhysRevB.76.224409

M3 - Article

VL - 76

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 22

M1 - 224409

ER -