Au<sub>55</sub>, a stable glassy cluster: results of ab initio calculations

Vollath, D.; Holec, David; Fischer, Franz Dieter

doi:10.3762/bjnano.8.222

Cited by 6 publications

(11 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The approach developed by Vollath et al [14] is based on the Kelvin equation and assumes, therefore, equilibrium with the vapor phase. However, at 0 K, this difference is not relevant.…”

Section: Reviewmentioning

confidence: 99%

“…The experimental error bar also covers the results of other authors. In this range, the particles are glassy, indicating a structure more stable than a crystalline one [ 13 – 14 ].…”

Section: Reviewmentioning

confidence: 99%

“…Furthermore, in many cases, nanoparticles exhibit a highly symmetrical structure as compared to the bulk material [ 50 ]. Nanoparticles may even exhibit a quasi-liquid or glassy structure, states having no equivalents in the bulk [ 14 ]. Recent calculations of the surface energy of gold as function of the particle size by Ali et al [ 51 ] have predicted an increase of the surface energy with decreasing particle size.…”

Section: Reviewmentioning

confidence: 99%

See 2 more Smart Citations

Surface energy of nanoparticles – influence of particle size and structure

Vollath¹,

Fischer²,

Holec³

2018

Beilstein J. Nanotechnol.

Self Cite

162

View full text Add to dashboard Cite

The surface energy, particularly for nanoparticles, is one of the most important quantities in understanding the thermodynamics of particles. Therefore, it is astonishing that there is still great uncertainty about its value. The uncertainty increases if one questions its dependence on particle size. Different approaches, such as classical thermodynamics calculations, molecular dynamics simulations, and ab initio calculations, exist to predict this quantity. Generally, considerations based on classical thermodynamics lead to the prediction of decreasing values of the surface energy with decreasing particle size. This phenomenon is caused by the reduced number of next neighbors of surface atoms with decreasing particle size, a phenomenon that is partly compensated by the reduction of the binding energy between the atoms with decreasing particle size. Furthermore, this compensating effect may be expected by the formation of a disordered or quasi-liquid layer at the surface. The atomistic approach, based either on molecular dynamics simulations or ab initio calculations, generally leads to values with an opposite tendency. However, it is shown that this result is based on an insufficient definition of the particle size. A more realistic definition of the particle size is possible only by a detailed analysis of the electronic structure obtained from initio calculations. Except for minor variations caused by changes in the structure, only a minor dependence of the surface energy on the particle size is found. The main conclusion of this work is that surface energy values for the equivalent bulk materials should be used if detailed data for nanoparticles are not available.

show abstract

“…The approach developed by Vollath et al [14] is based on the Kelvin equation and assumes, therefore, equilibrium with the vapor phase. However, at 0 K, this difference is not relevant.…”

Section: Reviewmentioning

confidence: 99%

“…The experimental error bar also covers the results of other authors. In this range, the particles are glassy, indicating a structure more stable than a crystalline one [ 13 – 14 ].…”

Section: Reviewmentioning

confidence: 99%

Section: Reviewmentioning

confidence: 99%

See 1 more Smart Citation

Surface energy of nanoparticles – influence of particle size and structure

Vollath¹,

Fischer²,

Holec³

2018

Beilstein J. Nanotechnol.

Self Cite

162

View full text Add to dashboard Cite

show abstract

“…Quite counterintuitively, the most preferable structure of a 55 Au atoms cluster was shown to be an amorphous structure even at 0 K [18], being a consequence of the small nanoparticle size. This prediction, however, was experimentally corroborated [18]. Ali et al [9] predicted a rapid increase of the surface energy upon the nanoparticle melting.…”

Section: Introductionmentioning

confidence: 99%

“…Their applications span from biomimetic materials, over printed electronics to electrochemical biosensors [16,17]. Quite counterintuitively, the most preferable structure of a 55 Au atoms cluster was shown to be an amorphous structure even at 0 K [18], being a consequence of the small nanoparticle size. This prediction, however, was experimentally corroborated [18].…”

Section: Introductionmentioning

confidence: 99%

Surface Energy of Au Nanoparticles Depending on Their Size and Shape

et al. 2020

Self Cite

View full text Add to dashboard Cite

Motivated by often contradictory literature reports on the dependence of the surface energy of gold nanoparticles on the variety of its size and shape, we performed an atomistic study combining molecular mechanics and ab initio calculations. We show that, in the case of Au nanocubes, their surface energy converges to the value for ( 0 0 1 ) facets of bulk crystals. A fast convergence to a single valued surface energy is predicted also for nanospheres. However, the value of the surface energy is larger in this case than that of any low-index surface facet of bulk Au crystal. This fact can be explained by the complex structure of the surface with an extensive number of broken bonds due to edge and corner atoms. A similar trend was obtained also for the case of cuboctahedrons. Since the exact surface area of the nanoparticles is an ill-defined quantity, we have introduced the surface-induced excess energy and discuss this quantity as a function of (i) number of atoms forming the nano-object or (ii) characteristic size of the nano-object. In case (i), a universal power-law behaviour was obtained independent of the nanoparticle shape. Importantly, we show that the size-dependence of the surface energy is hugely reduced, if the surface area correction is considered due to its expansion by the electronic cloud, a phenomenon specifically important for small nanoparticles.

show abstract