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We use molecular dynamics to calculate the structural, elastic, and polar properties of crystalline ferroelectric β-poly(vinylidene fluoride), PVDF (–CH2–CF2–)n with randomized trifluoroethylene TrFE (–CHF–CF2–)n as a function of TrFE content (0–50%) in the temperature range of 0–400 K. There is a very good agreement between the experimentally obtained and the computed values of the lattice parameters, thermal expansion coefficients, elastic constants, polarization, and pyroelectric coefficients. A continuous decrease in Young's modulus with increasing TrFE content was observed and attributed to the increased intramolecular and intermolecular repulsive interactions between fluorine atoms. The computed polarization displayed a similar trend, with the room temperature spontaneous polarization decreasing by 44% from 13.8 μC cm−2 (pure PVDF) to 7.7 μC cm−2 [50/50 poly(VDF-co-TrFE)]. Our results show …