Size-dependent melting and coalescence of tungsten nanoclusters via molecular dynamics simulation

Abstract

We obtained the melting temperatures of the W nanoclusters with diameters in the range of 2.5-5.0 nm which manifest the good linear fitting to the size of nanoclusters (N(-1/3)). Four different initial configurations at each size produce nearly the same melting points, with the maximum discrepancies less than 40 K. The extrapolated bulk melting point 4210 K is lower than the simulated bulk value 4520 K. Surface premelting is detected by density profiles, deformation parameters and bond orientational order parameters. Moreover, by dividing particles into surface and subsurface layers, we analyzed the different behaviors of the inner and outer shell atoms during melting in detail. During coalescence of W nanoclusters (W(N) + W(N)→ W(2N)), the shape change is along the path of peanut → rod-like → spherical → liquid structure. The obtained melting points from W(2N) are in good agreement with those from W(N) + W(N), indicating that melting temperatures are mainly relevant to the number of atoms, and nearly not affected by the different surface areas in nanoclusters.

Molecular Dynamics Simulation of the Coalescence and Melting Process of Cu and Ag Nanoparticles

“…During the application of nanoparticles, the coalescence and melting of nanoparticles may be an unavoidable problem. For the coalesce and melting process, it is difficult to observe them directly at the atomic scale through experiments [21]. erefore, many scholars [22][23][24] have used the MD method to simulate the melting process of pure metals and the coalescence and melting process of bimetallic nanoparticles.…”

Binding of hemoglobin to ultrafine carbon nanoparticles: a spectroscopic insight into a major health hazard

“…The domain of nanotechnology is rapidly increasing and today there are more than 1500 nanoproducts in the market. 1,2 The different nanostructured materials such as nanotubes, 3 nanoparticles, 2 nanocages, 4 nanopowders, 5 nanowires, 6 nanoshells, 7 nanorods, 8 nanobers, 9 quantum dots, 10 fullerenes, 11 liposomes, 12 neosomes, 13 nanoclusters, 14 nanomeshes, 15 nanocrystals, 16 nanolms 17 and nanocomposites 18 are internationally produced in bulk quantities because of their wide potential applications in skincare and consumer products, healthcare, photonics, electronics, biotechnology, engineering products, pharmaceuticals, drug delivery, agriculture, etc. When different nanostructured materials are exposed to the human body they can easily enter into the body through the lungs or other organs and tissues such as the brain, liver, kidney, heart, colon, bone and blood via food, drink and medicine.…”

Sintering reaction and microstructure of MAl (M = Ni, Fe, and Mg) nanoparticles through molecular dynamics simulation*

“…MD simulations of metal-cluster collision, coalescence, and sintering reaction have been extensively performed. [1,[8][9][10][11][12][13][14][15][16][17] Marcelo et al reported core-shell (PtAu), alloyed (PdAu), and onion-like (CuAg) cluster structures by colliding two different metal clusters at various initial velocities. [3] Yang et al simulated the sintering reaction between Li and Pd metal clusters at different initial temperatures [8] and found that metal nan-oclusters may undergo structural transformation during collision and coalescence, [1,18,19] Grammatikopoulos et al conducted a classical MD simulation of palladium (Pd) clusters' coalescence and performed magnetron sputtering of inert gas for the condensation deposition of Pd nanoparticles.…”