Morphological Changes of a Surface of Revolution due to Capillarity-Induced Surface Diffusion

Nichols, F.A.; Mullins, W. W.

doi:10.1063/1.1714360

Cited by 651 publications

(348 citation statements)

References 11 publications

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“…The standard analysis of kinetics of sintering is due to Mullins and Nichols [169,170]. The "motor" of the coalescence is the diffusion of atoms of the cluster (or island) surface from the regions of high curvature (where they have less neighbors and therefore are less bound) towards the regions of lower curvature.…”

Section: Continuum Theory Of Coalescencementioning

confidence: 99%

Growth of nanostructures by cluster deposition: Experiments and simple models

1999

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This paper presents a comprehensive analysis of simple models useful to analyze the growth of nanostructures obtained by cluster deposition. After detailing the potential interest of nanostructures, I extensively study the first stages of growth (the submonolayer regime) by kinetic MonteCarlo simulations. These simulations are performed in a wide variety of experimental situations : complete condensation, growth with reevaporation, nucleation on defects, total or null clustercluster coalescence . . . . The main scope of the paper is to help experimentalists analyzing their data to deduce which of those processes are important and to quantify them. A software including all these simulation programs is available at no cost on request to the author. I carefully discuss experiments of growth from cluster beams and show how the mobility of the clusters on the surface can be measured : surprisingly high values are found. An important issue for future technological applications of cluster deposition is the relation between the size of the incident clusters and the size of the islands obtained on the substrate. An approximate formula which gives the ratio of the two sizes as a function of the melting temperature of the material deposited is given. Finally, I study the atomic mechanisms which can explain the diffusion of the clusters on a substrate and the result of their mutual interaction (simple juxtaposition, partial or total coalescence . . . ).

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Section: Continuum Theory Of Coalescencementioning

confidence: 99%

Growth of nanostructures by cluster deposition: Experiments and simple models

1999

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“…intergranular phase characterized by a dihedral angle ~, the ratio A . /21TR normalizes the actual A. by the minimum wavelength that mln eq mln 8 . .…”

Section: Determination Of Surface Areamentioning

confidence: 99%

“…Among these are: the stability of lamellar eutectics 3 , fibers in composites 4 • artificially lengthened precipitates 5 ,6, shape evolution of field ion emitter tips7, 8 While in some of the aforementioned ap·plications the Rayleigh analysis may be valid. complications arise when the continuous phase is located at a grain boundary.…”

Section: Introductionmentioning

confidence: 99%

The Morphological Stability of Continuous Intergranular Phases

Carter

Glaeser

1986

Tailoring Multiphase and Composite Ceramics

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“…The general process of intercluster coalescence has been extensively studied using molecular dynamics [3][4][5] or by macroscopic models of sintering [6]. This process is driven by capillarity since it reduces the surface free energy.…”

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confidence: 99%

“…Below a certain size (≤20 nm of diameter), clusters of cobalt crystallize in the face-centered cubic (fcc) phase and most particles possess crystalline structures made up of multiply-twinned icosahedra [2]. Besides, these nanoparticles are converted into single-crystal Wulff polyhedra above 300ºC.The general process of intercluster coalescence has been extensively studied using molecular dynamics [3][4][5] or by macroscopic models of sintering [6]. This process is driven by capillarity since it reduces the surface free energy.…”

mentioning

confidence: 99%

Nanoparticle heterocoalescence induced by deposition

Jiménez-Sáez¹,

Ettaoussi

Pérez-Martı́n

et al. 2010

Phys. Status Solidi (c)

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Cobalt in nanocrystalline form is an attractive system because it displays a wealth of sizedependent structural, magnetic, electronic, and catalytic properties [1]. From a technological viewpoint, Co nanoparticles have applications in magnetic storage media. Below a certain size (≤20 nm of diameter), clusters of cobalt crystallize in the face-centered cubic (fcc) phase and most particles possess crystalline structures made up of multiply-twinned icosahedra [2]. Besides, these nanoparticles are converted into single-crystal Wulff polyhedra above 300ºC.The general process of intercluster coalescence has been extensively studied using molecular dynamics [3][4][5] or by macroscopic models of sintering [6]. This process is driven by capillarity since it reduces the surface free energy. Specifically, the coalescence of supported clusters is of great importance in the field of surface nanostructuring [7]. Kellet and Lange [8,9] indicated that, in the case of the presence of grain boundaries between particles, a further lowering of the free energy would require the recrystallization of some particles. Therefore, atomistic models describing coalescence must account for changing crystallographic mismatch. Many groups have performed crystallite rotation techniques in order to investigate the reorientation during sintering for metals [10][11][12][13][14] and oxide particles [15,16]. For metals, the mechanism of reorientation may then include the formation or migration of grain-boundary dislocations.In the present work, the coalescence between Co and Cu clusters on Cu(001) substrate is studied by constant-temperature molecular dynamics simulations. Cobalt clusters embedded or supported in a copper matrix constitute an attractive system, because it displays important magnetic properties [17,18]. Atomic interactions are mimicked by a many-body potential based on the second-moment tight-binding approximation (TB-SMA). Initially, Co clusters of about half a thousand of atoms in their more stable form were deposited on a Cu (001) substrate at 250 meV/atom and room temperature. Next, a randomly oriented Cu cluster of the same size at 250 meV/atom with icosahedral or cuboctahedral form and fcc phase was deposited on the former colliding with this at room temperature. The center-of-mass separation between the projectile and target clusters was varied uniformly. The degree of epitaxy of the two clusters has been investigated as a function of this separation, and of the type of material. The effect of the temperature as activation of grain-boundary movement to get the complete epitaxy has been also analyzed in the projectile cluster.Nanoparticle coalescence has theoretically as well as experimentally been shown to be a twostep process: first a reorientation of adjacent nanoparticles, and second a complete or incomplete adhesion depending on the matching of the crystallographic orientations [16]. This work is mainly focused on the first process, since the appearance, movement, and disappearance of grains after the collision has been de...

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Morphological Changes of a Surface of Revolution due to Capillarity-Induced Surface Diffusion

Cited by 651 publications

References 11 publications

Growth of nanostructures by cluster deposition: Experiments and simple models

Growth of nanostructures by cluster deposition: Experiments and simple models

The Morphological Stability of Continuous Intergranular Phases

Nanoparticle heterocoalescence induced by deposition

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