ABSTRACT
Atomic structure, thermodynamic and mechanical behaviours of the penta-silicene (p-silicene) obtained by cooling from the melt are studied by the molecular dynamics (MD) simulations. We find that p-silicene can ‘naturally’ form from the liquid state using the appropriate interatomic potential, density and buckling. The charge-optimised many body (COMB) potential is employed. Depending on the cooling rate used in simulations, ‘crystalline’ or amorphous p-silicene can be obtained. ‘Crystallisation’ and glass transition temperatures ( and
, respectively) have reasonable values compared to those of the hexa-silicene (h-silicene). We find that the Poisson’s ratio of the obtained ‘crystalline’ p-silicene is positive unlike the negative one found for the p-graphene. The reasons for the formation of p-silicene instead of tetra-silicene (t-silicene) are analysed and discussed, i.e. 2D liquid silicene with COMB potential has a significant fraction of pentagons which grow with decreasing temperature, unlike 2D liquid silicene with the Stillinger–Weber potential.
Acknowledgements
This research is funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant 103.01-2017.01.
Disclosure statement
No potential conflict of interest was reported by the author(s).