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The ferroelectricity of P(VDF?TrFE) has been well expressed by the molecular dynamics simulations.AbstractWe present a molecular dynamics simulation method including x?ray diffractometer pattern calculation, mean square displacement (MSD), and nonbonding energy distribution (NED) to disclose the dependencies of condensed structure on its crystalline process of the poly(vinylidene fluoride?trifluoroethylene) (P(VDF?TrFE)) films. For comparison, the P(VDF?TrFE) solution is casted into the films, and followed that different thermal processes are performed to fabricate the crystalline states of the films. Simulation and experimental results have good consistency, indicating that high temperature annealing can effectively promote all?trans ? phase in the crystal region of P(VDF?TrFE). As such, P(VDF?TrFE) 80/20?mol% annealing at 140°C shows a higher MSD (~27.5?Å2) and a faster reducing rate of NED than that of other films, contributing to a large maximum polarization (Ps) of ~15.5??C?cm?2, high a remnant polarization (Pr) of ~11.8??C?cm?2, and an attractive piezoelectric strain coefficient (d33) of ?27.1?pC?N?1 under 200?MV?m?1, respectively, and providing a reference for the applications of P(VDF?TrFE) in flexible sensors, actuators, transducers, and so forth.