Cluster melting molecular dynamics

F. Ding, A. Rosen, K. Bolton, Size dependence of the coalescence and melting of iron clusters a molecular-dynamics study. Phys. Rev. B 70(7), 075416 (2004)... 

Soule de Bas, B., Ford, M.J. and Cortie, M.B. (2006) Melting in small gold clusters a Density Functional molecular dynamics study. Journal of Physics -Condensed Matter, 18, 55-74. 

In a molecular dynamic simulation147 of bulk atomic diffusion by a vacancy mechanism, two atoms may occasionally jump together as a pair. The temperature of the simulation is close to the melting point of the crystal. In FTM studies of single atom and atomic cluster diffusion, the temperature is only about one tenth the melting point of the substrate. All cluster diffusion, except that in the (1 x 1) to (1 x 2) surface reconstruction of Pt and Ir (110) surfaces already discussed in Section 4.1.2(b), are consistent with mechanisms based on jumps of individual atoms.148,149 In fact, jumps of individual atoms in the coupled motion of adatoms in the adjacent channel of the W (112) surface can be directly seen in the FTM if the temperature of the tip is raised to near 270 K.150... 

This study presents the results of the molecular-dynamics simulation of Ni, Cu and Au in liquid and supercooled liquid states using realistic potentials of interatomic interaction. At supercooling of melt, the structure analysis of the evolution of the local cluster structure has been performed on the basis of the parameters of the orientation order of interatomic bonds and the coordination numbers. The presence of local icosahedral and... 

Using ab initio, density-functional, molecular-dynamics calculations on the Nuat clusters, Zorriasatein et al studied also the thermodynamic properties of those. As discussed above for the study of Eryiirek and Giiven, also Zorriasatein et al. found that the melting temperature depends in a highly non-trivial way on the cluster size. 

In order to study the dynamics of small sodium clusters at finite temperatares Born-Oppenheimer molecular dynamics (BOMD) calculations were performed at the above described PBE/DZVP/A2 level of theory. For each cluster, from the dimer to the nonamer, 18 trajectories were recorded in a temperature range from 50 to 900 K with intervals of 50 K. Each trajectory has a length of 220 ps and was recorded with a time step of 2 ps. Similar statistics have already been successfully applied to determine the melting temperatures of sodium clusters with LDA pseudo-potential DFT molecular dynamics (Chacko et al. 2005). 

Garcia-Rodeja, J., Rey> C.> Gallego, L. J.> Alonso, J. A. (1994). Molecular-dynamics study of the structures, binding energies, and melting of clusters of fee transition and noble metals using the voter and chen version of the embedded-atom model. Physical Review B, 49, 8495. 

L. Miao, V.R. Bhethanabotla, B. Joseph, Melting of Pd clusters and nanowires A comparison study using molecular dynamics simulation. Phys. Rev. B 72(13), 134109 (2005)... 

The pneumatic assistance or expanding bubble model " cluster model. Its main feature is also mechanical separation of preformed ions during ablation, by gas bubbles forming below the surface. When these burst, small droplets or fragments are ejected, which then evolve to give individual ions as in other cluster models. Subsurface nucleation driving ablation of overlying melt has also been noted in molecular dynamics simulations, and the bubble chamber FAB/SIMS model is very similar. " " ... 

Kumar et al used spectroscopic techniques such as NMR to study the properties and structures of mixed glass systems. Rosenhahn et al. obtained insight into the structure and dynamics of the binary As-Se glass system from high temperature Se NMR studies of molten salts. Ab initio molecular orbital calculations have been carried out for sihcate, aluminosilicate and aluminate clusters to study the NMR characteristics of various types of hydroxyl that are possibly present in hydrous silicate glasses and melts. Xue and Kanzaki in particular studied the specification and dynamics of dissolved water in the silicate glasses. 

The epoxidation of ethylene which is catalyzed by Ag and promoted by chlorine compounds, for example, is thought to occur in a surface overlayer that has features similar to a melt of Ag ions. The silver-oxychloride reactive surface layer requires Ag + ions (as in the electrochemical system, see Scheme 2.1) to enhance the overall selectivity. Reduced Ag clusters, however, are required to activate molecular oxygen. Dynamic events between these two states are necessary to close the catalytic cycle. Chlorine in combination with Cs is added to promote the Ag catalyst. Eutectic melting points of this phase are close to the reaction temperature 14]... 

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