Several static and dynamic properties of liquid magnesium near melting have been evaluated by the orbital-free ab initio molecular dynamics method. The calculated static structure shows good agreement with recent experimental data, including an asymmetric second peak in the structure factor which has been linked to the existence of an important icosahedral short-range order in the liquid. As for the dynamic structure, we obtain collective density excitations with an associated dispersion relation which closely follows recent experimental results. Accurate estimates have also been obtained for several transport coefficients.

No abstract

No abstract

No abstract

No abstract

In this study, the atomic structure and the glass formation process of Co 90 Zr 10 metallic glass alloy were studied by molecular dynamic simulation based on the embedded atom method using four different cooling rates. The average atomic volume and the potential energy of the system were observed to be strongly dependent on the cooling rate during rapid solidification, and the glass transition temperature decreased with decreasing cooling rate. The radial distribution functions and the structure factors derived from molecular dynamics simulations at 300 K agreed well with the experimental and other molecular dynamics results. The coordination numbers calculated at 300 K were consistent with the experimental results in the literature. The local structural atomic orders of the system have been characterized by Honeycutt-Andersen indices and the Voronoi tessellation method. We realized that the FCC and icosahedral shortrange order increases with decreasing cooling rate, the icosahedral clusters are predominant in the Co 90 Zr 10 metallic glass, and the fraction of the icosahedral polyhedra increases with decreasing cooling rate and temperature. We have seen that Co-centered Voronoi polyhedrals such as ⟨ 0,2,8,2 ⟩ , ⟨ 0,0,12,0 ⟩ , and ⟨ 0,1,10,2 ⟩ play a dominant role in the development of the icosahedral order of the Co 90 Zr 10 alloy.

No abstract

No abstract