Heating-induced phase transitions in confined amorphous tetra-silicene

Abstract

Heating-induced phase transitions of confined amorphous tetra-silicene (t-silicene) are studied via molecular dynamics (MD) simulations. Glassy models containing 6066 atoms interacted via Stillinger-Weber potential are heated up from 300 K to 5000 K at the heating rate of 1011 K s−1. We find glass-crystal-liquid phase transition indicated that amorphous t-silicene is a less stable glass. Crystallization of amorphous t-silicene occurs at around K while subsequent melting of crystallized t-silicene appears at around K. The latter is close to that of hexa-silicene. Thermodynamics and evolution of structure of models upon heating are analyzed in details. We find that crystallization of amorphous t-silicene occurs via homogeneous local rearrangements of atoms in the glassy matrix. Atomic mechanism of crystallization and subsequent melting of the obtained crystalline t-silicene is studied and the role of liquid-like atoms in this phase transition is clarified.