Pressure-induced structural phase transitions in a two-dimensional system
نویسندگان
چکیده
We have performed molecular-dynamics simulation to analyze structural phase transitions in a twodimensional system using a model which has been proposed to study pressure-induced martensitic transformation in iron. At low temperatures, the square↔hexagonal phase transition was observed at P =5.4 1 and the reverse transition occurred only by application of tension on the system. At a temperature near the melting point, the hexagonal phase was reached at P =3.1 1 and it went back to square symmetry at P =1.9 1 showing hysteresis. The activation energy for this transition was evaluated using the nudged elastic band method. Our work permitted to detail the mechanism of square↔hexagonal transformations, contributing for a better understanding about the dynamics of self-organization phenomenon.
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