The Melting Behaviors of the Bimetallic Cluster ConCu55-n(n=0~55)

2014 ◽  
Vol 909 ◽  
pp. 32-35
Author(s):  
Qian Li ◽  
Li Liu ◽  
Ying Jin Feng ◽  
Shi Feng Zhang

The melting behaviors of ConCu55-n(n=0~55) bimetallic cluster were studied by using semi-empirical Gupta potential combined with molecular dynamics simulations. The melting point of the ConCu55-n(n=0~55) cluster shows itself the trend of going up, accompanied by the increasing of the Cobalt atomicity. However, it is between Co55 and Cu55 elementary cluster for melting point overall. Meanwhile the variation in the width of pre-melting temperature is greater, if around n0 or n55, but it is lesser nearly n55/2(namely Co and Cu at the same atomicity). In addition, the saturation point of specific heat capacity can be determined corresponding to the peak of Lindemann index.

2013 ◽  
Vol 423-426 ◽  
pp. 935-938 ◽  
Author(s):  
Ji Feng Li ◽  
Xiao Ping Zhao ◽  
Jian Liu

Molecular dynamics simulations were performed to calculate the melting points of perfect crystalline aluminum to high pressures. Under ambientpressure, there exhibits about 20% superheating before melting compared to the experimental melting point. Under high pressures, thecalculated melting temperature increases with the pressure but at a decreasing rate, which agrees well with the Simon's melting equation. Porosity effect was also studied for aluminum crystals with various initial porosity at ambient pressure, which shows that the equilibrium melting point decreases with the initial porosity as experiments expect.


Author(s):  
Majid S. al-Dosari ◽  
D. G. Walker

Yttrium Aluminum Garnet (YAG, Y3Al5O12) and its varieties have applications in thermographic phosphors, lasing mediums, and thermal barriers. In this work, thermal properties of crystalline YAG where aluminum atoms are substituted with gallium atoms (Y3(Al1−xGax)5O12) are explored with molecular dynamics simulations. For YAG at 300K, the simulations gave values close to experimental values for constant-pressure specific heat, thermal expansion, and bulk thermal conductivity. For various values of x, the simulations predicted no change in thermal expansion, an increase in specific heat, and a decrease in thermal conductivity for x = 50%. Furthermore, the simulations predicted a decrease in thermal conductivity with decreasing system size.


2021 ◽  
Author(s):  
Xue-Qi Lv ◽  
Xiong-Ying Li

Abstract The melting at the magnesium/aluminum (Mg/Al) interface is an essential step during the fabrications of Mg-Al structural materials and biomaterials. We carried out molecular dynamics simulations on the melting at the Mg/Al interface in a Mg-Al-Mg nanolayer via analyzing the changes of average atomic potential energy, Lindemann index, heat capacity, atomic density distribution and radial distribution function with temperature. The melting temperatures (T m) of the nanolayer and the slabs near the interface are significantly sensitive to the heating rate (v h) over the range of v h≤4.0 K/ps. The distance (d) range in which the interface affects the melting of the slabs is predicted to be (-98.2, 89.9) Å at v h→0, if the interface is put at d=0 and Mg (Al) is located at the left (right) side of the interface. The (T m) of the Mg (Al) slab just near the interface (e.g., d=4.0 Å) is predicted to be 926.8 K (926.6 K) at v h→0, with 36.9 K (37.1 K) below 963.7 K for the nanolayer. These results highlight the importance of regional research on the melting at an interface in the nanolayers consisting of two different metals.


2014 ◽  
Vol 16 (21) ◽  
pp. 9760-9775 ◽  
Author(s):  
R. B. Gerber ◽  
D. Shemesh ◽  
M. E. Varner ◽  
J. Kalinowski ◽  
B. Hirshberg

Recent progress in “on-the-fly” trajectory simulations of molecular reactions, using different electronic structure methods is discussed, with analysis of the insights that such calculations can provide and of the strengths and limitations of the algorithms available.


Sign in / Sign up

Export Citation Format

Share Document