Quantum spins in Mackay icosahedral gold nanoparticles

Wu, Chun‐Ming; Li, Chi-Yen; Kuo, Yen‐Ting; Wang, Chin-Wei; Wu, Shang Liang; Li, Wen-Hsien

doi:10.1007/s11051-009-9592-3

Cited by 28 publications

(23 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, recent models proposed to explain the magnetism in Au as from orbital origin, that consider quasifree electrons or holes [25,26] from the 6sp conduction band, or unpairing of quantumconfined conduction electrons excited thermally [27], cannot explain our experimental results.…”

mentioning

confidence: 55%

Strong Paramagnetism of Gold Nanoparticles Deposited on aSulfolobus acidocaldariusSLayer

Bartolomé

Garcı́a

et al. 2012

Phys. Rev. Lett.

View full text Add to dashboard Cite

Magnetic properties of Au nanoparticles deposited on an archaeal S layer are reported. X-ray magnetic circular dichroism and superconducting quantum interference device magnetometries demonstrate that the particles are strongly paramagnetic, without any indication of magnetic blocking down to 16 mK. The average magnetic moment per particle is M part ¼ 2:36ð7Þ B . This contribution originates at the particle's Au 5d band, in which an increased number of holes with respect to the bulk value is observed. The magnetic moment per Au atom is 25 times larger than any measured in other Au nanoparticles or any other configurations up to date.

show abstract

mentioning

confidence: 55%

Strong Paramagnetism of Gold Nanoparticles Deposited on aSulfolobus acidocaldariusSLayer

Bartolomé

Garcı́a

et al. 2012

Phys. Rev. Lett.

View full text Add to dashboard Cite

show abstract

“…[3] They are, however, higher than those reported for icosahedral Au nanoparticles by Wu et al [11] All particles up to 15 nm diameter are ferromagnetic with considerable coercive field. Both M S and M R decrease with increasing particle diameter (Figure 3 a), the values of M S and M R having been calculated after subtracting the diamagnetic signal from the Au core and sample holder.…”

Section: Resultsmentioning

confidence: 88%

“…Such breaks in the M-T curves have been considered to arise from interactions between core and surface spins in Au nanoparticles, with the spins pointing in opposite directions. [11] The smaller the particle size, the greater the interaction between core and surface spins, and therefore a higher temperature is required to remove these interactions. In the case of thiol-capped nanoparticles the interaction is greater, which results in a shift of the jump to higher temperatures along with increase in sharpness of the jump.…”

Section: Resultsmentioning

confidence: 99%

“…While it would seem that the presence of thiol or amine capping agents is necessary for the magnetism of Au nanoparticles on the basis of some of the reports, Reich et al [10] observed magnetism in 27 nm thin films of Au deposited on Pyrex glass. More recently, Wu et al [11] reported that icosahedral gold nanoparticles prepared by the gas-condensation method are ferromagnetic, whereby the moments of the core and surface atoms point in opposite directions.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ferromagnetism Exhibited by Nanoparticles of Noble Metals

et al. 2011

View full text Add to dashboard Cite

Gold nanoparticles with average diameters in the range 2.5-15 nm, prepared at the organic/aqueous interface by using tetrakis(hydroxymethyl)phosphonium chloride (THPC) as reducing agent, exhibit ferromagnetism whereby the saturation magnetization M(S) increases with decreasing diameter and varies linearly with the fraction of surface atoms. The value of M(S) is higher when the particles are present as a film instead of as a sol. Capping with strongly interacting ligands such as alkane thiols results in a higher M(S) value, which varies with the strength of the metal-sulfur bond. Ferromagnetism is also found in Pt and Ag nanoparticles prepared as sols, and the M(S) values vary as Pt>Au>Ag. A careful study of the temperature variation of the magnetization of Au nanoparticles, along with certain other observations, suggests that small bare nanoparticles of noble metals could indeed possess ferromagnetism, albeit weak, which is accentuated in the presence of capping agents, specially alkane thiols which form strong metal-sulfur bonds.

show abstract

“…Magnetism is observed in thiol-capped GNPs, [12][13][14] yet it is often attributed primarily to the gold sulfur bond present in such compounds instead of the finite size of the GNP. There are only a few studies investigating magnetism in uncapped GNPs, [15][16][17][18] and with para-, ferro-, and ferrimagnetism reported, there is no consensus.…”

mentioning

confidence: 99%

Communication: Chemisorption of muonium on gold nanoparticles: A sensitive new probe of surface magnetism and reactivity

Dehn

Arseneau

Böni

et al. 2016

The Journal of Chemical Physics

View full text Add to dashboard Cite

Chemisorption of muonium onto the surface of gold nanoparticles has been observed. Muonium (μ+e−), a light hydrogen-like atom, reacts chemically with uncapped 7 nm gold nanoparticles embedded in mesoporous silica (SBA-15) with a strong temperature-dependent rate. The addition rate is fast enough to allow coherent spin transfer into a diamagnetic muon state on the nanoparticle surface. The muon is well established as a sensitive probe of static or slowly fluctuating magnetic fields in bulk matter. These results represent the first muon spin rotation signal on a nanoparticle surface or any metallic surface. Only weak magnetic effects are seen on the surface of these Au nanoparticles consistent with Pauli paramagnetism.

show abstract

Quantum spins in Mackay icosahedral gold nanoparticles

Cited by 28 publications

References 18 publications

Strong Paramagnetism of Gold Nanoparticles Deposited on aSulfolobus acidocaldariusSLayer

Strong Paramagnetism of Gold Nanoparticles Deposited on aSulfolobus acidocaldariusSLayer

Ferromagnetism Exhibited by Nanoparticles of Noble Metals

Communication: Chemisorption of muonium on gold nanoparticles: A sensitive new probe of surface magnetism and reactivity

Contact Info

Product

Resources

About