Program

P.56 -- Poster, NCTP-42

Date: Wednesday, 2 August 2017

Time: 08h30 - 10h00

Cooling rate effect and size effect on formation of two-dimensional SiC from the liquid state

Truong Quoc Tuan1, Huynh Anh Huy2, Vo Van Hoang3, Ong Kim Le1

1Dept. of Physics, Faculty of Natural Sci., Can Tho Univ., Can Tho - Vietnam Email: truongquoctuanvl@gmail.com 2Dept. of Physics, Faculty of Education, Can Tho Univ., Can Tho-Vietnam 3Comp. Phys. Lab, HoChiMinh City Univ. of Technology, Vietnam National University – HoChiMinh City

Abstract We present molecular dynamics (MD) simulations of formation of SiC from liquid state. The initial systems (containing 3000 and 9968 atoms Si and C) are arranged a planar with honeycomb structure and under periodic boundary conditions. The particles in the models interacted via Tersoff potential (Phys. Rev. B 39, 5566, 1989). Models are heated to temperature much higher melting point in order to get liquid state. Then, models are cooled down to 300 K. Evolution of structure and thermodynamic properties upon cooling/heating are found and discussed such as radial distribution functions (RDF), temperature dependence of total energy, potential and kinetic energy, volume and mass density, ratio between volume at given temperature and initial volume, bond-angle distribution, interatomic distance between Si-C, Si-Si and C-C bonding, ring size distribution, mean of coordination number Si (total), C (total) and partial coordination number Si(C), Si(Si), C(Si), C(C). 2D visualization of atomic configurations are also presented. Formation of 2D-SiC from the liquid state has been effected by size of model and cooling rate. The atoms with a same style have a tendency to aggregate into clusters, we find the existence of some small graphene (formation of species of only C-C binding in honeycomb structure) and silicene domains in the models of SiC obtained at 300 K (formation of species of only Si-Si binding in honeycomb structure). All the models received at 300 K are amorphous SiC. Acknowledgements This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant 103.02-2016.88.

Presenter: Truong Quoc Tuan