相关论文: Characterizing the greater-than-bulk melting behav…
Employing first principles parallel tempering molecular dynamics in the microcanonical ensemble, we report the presence of a clear solid-liquid-like melting transition in Al20+ clusters, not found in experiments. The phase transition…
Experiments and simulations have been performed to examine the finite-temperature behavior of Ga$_{17}{}^{+}$ and Ga$_{20}{}^{+}$ clusters. Specific heats and average collision cross sections have been measured as a function of temperature,…
Density functional molecular dynamical simulations have been performed on Ga$_{17}$ and Ga$_{13}$ clusters to understand the recently observed higher-than-bulk melting temperatures in small gallium clusters [Breaux {\em et al.}, Phys. Rev.…
Phase field crystal methodology is applied, for the first time, to study the effect of alloy composition on the clustering behavior of a quenched/aged supersaturated ternary Al alloy system. An analysis of the work of formation is built…
Composition, atomic structure, and electronic properties of TM$_x$Mg$_y$O$_z$ clusters (TM = Cr, Ni, Fe, Co, $x+y \leq 3$) at realistic temperature $T$ and partial oxygen pressure $p_{\textrm{O}_2}$ conditions are explored using the {\em ab…
A coarsened model for a binary system with limited miscibility of components is proposed; the system is described in terms of structural states in small parts of the material. The material is assumed to have two alternative types of…
A unique property of size-resolved metal nanocluster particles is their "superatom"-like electronic shell structure. The shell levels are highly degenerate, and it has been predicted that this can enable exceptionally strong…
A dimer of bound atoms cannot melt, only dissociate. Bulk metals show a well defined first order transition between their solid and liquid phases. The appearance of the melting transition is explored for increasing clusters sizes via the…
The phase stability of NiAl clusters of nanometer size was studied by using the embedded atom model and Monte Carlo simulation techniques. For temperatures of 500 and 1000 K and for a range of compositions below 70 at.% Al, the equilibrium…
A unique property of metal nanoclusters is the "superatom" shell structure of their delocalized electrons. The electronic shell levels are highly degenerate and therefore represent sharp peaks in the density of states. This can enable…
We study the thermodynamics of Na_8 and Na_{20} clusters using multiple-histogram methods and an ab initio treatment of the valence electrons within density functional theory. We consider the influence of various electron kinetic-energy…
The approximate location in the Zaanen-Sawatzky-Allen diagram of the phase-separated (Ga,Mn)As material, consisting of MnAs nanoclusters embedded in GaAs, is determined on the basis of configuration-interaction (CI) cluster-model analysis…
At the nanoscale, materials exhibit unique properties that differ greatly from those of the bulk state. In the case of Ag$_x$Pt$_{1-x}$ nanoalloys, we aimed to study the solid-liquid transition of nanoparticles of different sizes and…
We study analytically the intricate phase behavior of cross-linked $AB$ diblock copolymer melts, which can undergo two main phase transitions due to quenched random constraints: Gelation, i.e., spatially random localization of polymers…
From systematic ab initio calculations of the alloy system Mg_{1-x}Al_{x}B_2, we find a strong tendency for the formation of a superstructure characterized by Al-rich layers. We also present a simple model, based on calculated energies and…
Materials composed of elements from the third and fifth columns of the periodic table display a very rich behavior, with the phase diagram usually containing a metallic liquid phase and a polar semiconducting solid. As a consequence, it is…
We determine the structure and melting behavior of supported metallic clusters using an ab initio density-functional-based treatment of intracluster interactions and an approximate treatment of the surface as an idealized smooth plane…
In this work, the melting phase transitions of $Fe_{n}$ nanoclusters with $10 \leq n \leq 100$ atoms are investigated using classical many-body molecular dynamics simulations. For many cluster sizes, surface melting occurs at much lower…
We study the coalescence of nanoscale metal clusters in an inert-gas atmosphere using constant-energy molecular dynamics. The coalescence proceeds via atomic diffusion with the release of surface energy raising the temperature. If the…
The thermodynamic properties of {\alpha}-Al and other phases (GP zones, {\theta}'', {\theta}' and {\theta}) in the Al-rich part of the Al-Cu system have been obtained by means of the cluster expansion formalism in combination with…