相关论文: Surface Nucleation in the Freezing of Gold Nanopar…
We examine the metastable liquid phase of a supercooled gold nanocluster by studying the free energy landscape using the largest solid-like embryo as an order parameter. Just below freezing, the free energy exhibits a local minimum at small…
The thermodynamics and kinetics of crystallization of nanoparticles, as opposed to bulk phases, may be influenced by surface and size effects. We investigate the importance of such factors in the crystallization process of gold, silver, and…
We use molecular dynamics simulations to study the melting of gold icosahedral clusters of a few thousand atoms. We pay particular attention to the behavior of surface atoms, and to the equilibrium shape of the cluster. We find that…
We simulate the homogeneous nucleation of ice from supercooled liquid water at 220 K in the isobaric-isothermal ensemble using the MW monatomic water potential. Monte Carlo simulations using umbrella sampling are performed in order to…
We study the nucleation of crystalline cluster phases in the generalized exponential model with exponent n=4. Due to the finite value of this pair potential for zero separation, at high densities the system forms cluster crystals with…
We present a detailed molecular-dynamics study of the melting, freezing, and coalescence of gold nanoclusters within the framework of the embedded-atom method. Concerning melting, we find the process to first affect the surface…
We present measurements of growth rates of the (0001) facet surface of ice as a function of water vapor supersaturation over the temperature range $-2$ $\geq T\geq -40$ C. From these data we infer the temperature dependence of premelting on…
We examine ice crystal growth from water vapor at temperatures near the melting point, when surface premelting creates a quasiliquid layer at the solid/vapor interface. Recent ice growth measurements as a function of vapor supersaturation…
Crystallization and vitrification of tetrahedral liquids are important both from a fundamental and a technological point of view. Here, we study via extensive umbrella sampling Monte Carlo computer simulations the nucleation barriers for a…
The crystallisation of entangled polymers from their melt is investigated using computer simulation with a coarse-grained model. Using hybrid Monte Carlo simulations enables us to probe the behaviour of long polymer chains. We identify…
Among all the freezing transitions, that of water into ice is probably the most relevant to biology, physics, geology or atmospheric science. In this work we investigate homogeneous ice nucleation by means of computer simulations. We…
The crystal nucleation from liquid in most cases is too rare to be accessed within the limited timescales of the conventional molecular dynamics (MD) simulation. Here, we developed a "persistent embryo" method to facilitate crystal…
The freezing behavior of gold nanoclusters was studied by employing molecular dynamics simulations based on a semi-empirical embedded-atom method. Investigations of the gold nanoclusters revealed that, just after freezing, ordered…
The basic physics of nucleation in solid \hl{single-crystal} nanoparticles is revealed by a phase-field theory that includes surface energy, chemical reactions and coherency strain. In contrast to binary fluids, which form arbitrary contact…
Molecular dynamic simulations are used to study the heating of a gold nanorod of 2624 atoms. We show that roughening of surface {110} facets leads to a shape transformation and structural rearrangement of surface and bulk atoms in the rod,…
The simulation and analysis of the thermal stability of nanoparticles, a stepping stone towards their application in technological devices, require fast and accurate force fields, in conjunction with effective characterisation methods. In…
Nucleation and growth of solids from solutions impacts many natural processes and are fundamental to applications in materials engineering and medicine. For a crystalline solid, the nucleus is a nanoscale cluster of ordered atoms, which…
Molecular dynamics simulations show that gold clusters with about 600--3000 atoms crystallize into a Mackay icosahedron upon cooling from the liquid. A detailed surface analysis shows that the facets on the surface of the Mackay icosahedral…
In standard nucleation theory, the nucleation process is characterized by computing $\Delta\Omega(V)$, the reversible work required to form a cluster of volume $V$ of the stable phase inside the metastable mother phase. However, other…
The freezing of metal nanoclusters such as gold, silver, and copper exhibits a novel structural evolution. The formation of the icosahedral (Ih) structure is dominant despite its energetic metastability. This important phenomenon, hitherto…