Pressure-induced ferroelectric phase transition in Bi4Ti3O12: a molecular dynamics study
We have studied pressure-induced phase transition of Bi4Ti3O12 (BIT) using a shell model via molecular dynamics method. We added the Ti-Ti short range interaction potential in an effort to increase the accuracy of the simulation. The calculated spontaneous polarizations of ferroelectric orthorhombic B2cb phase BIT single crystal are 39.4 μC/cm2 in the x direction and 0 μC/cm2 in the z direction at 300 K, which are in reasonable agreement with the experimental values. We also calculated the pressure-induced phase transition of BIT. It is observed that BIT single crystal undergoes two structural transformations at around 6 Gpa and 20 Gpa with increasing pressure from -2 Gpa to 24 Gpa. The accompanying symmetry changes may be the same as those observed at ambient pressure at elevated temperature. Our results thus provide a theoretical prediction of the pressure-induced phase transition in BIT which is not yet observed experimentally.
Bi4Ti3O12 pressure phase transition
SUN Lingling MA Ying ZHOU Yichun
Key Laboratory of Low Di-mensional Materials and Application Technology of Ministry of Education，Fac
国内会议
长沙
英文
1-1
2010-06-19（万方平台首次上网日期，不代表论文的发表时间）