Programme

P.13 -- Poster, NCTP-43

Date: Tuesday, 31 July 2018

Time: 08:30 - 10:00

Amorphous Silicon Carbide: a View from Molecular Dynamics Simulation

Vo Van On (1), Nguyen Hoang Giang (1,2), Vo Van Hoang (2), Huynh Thi Phuong Thuy (1)

(1) Group of Computational Physics and Simulation advanced materials – Faculty of Natural Sciences - University of Thu Dau Mot (2) Computational Physics Laboratory, Institute of Technology, Vietnam National University-Ho Chi Minh

In this research, Models of amorphous silicon carbide (a-SiC) containing 8000 atoms Si and C at a ratio of 50:50 are obtained by cooling from the melt via molecular dynamics (MD) simulation. The evolution of various kinds of structural and thermodynamic behaviors in models upon cooling from the melt is found, including total energy, radial distribution function (RDF), interatomic distance, coordination number, and ring and bond-angle distributions. The glass transition temperature of 2D silicon carbide(Tg = 3017 K) has a reasonable value compared to that of its 3D counterpart. Calculations show that although most atoms in a-silicon carbide obtained at 300 K have a coordination Z =3 and mainly evolve into six-fold rings, a-silicon carbide also contains various structural defects including those not found in crystalline silicon carbide (c-SiC) such as adatoms, clusters of small-membered rings, large-membered rings and local linear defects. The concentration of defects in a-silicene is higher than that of the crystalline version. We find that buckling is not unique for all the atoms in the model. The strong distorted structure of a-silicon carbide compared to that of the crystalline version may lead to new physico-chemical properties differed from those of c-SiC. Key Words: amorphous silicon carbide, SiC, 2D amorphous materials, liquid–glass transition

Presenter: On Van Vo