“…3 Most of the extensively studied ferroelastic materials are inorganic metal oxides, such as PrAlO 3 , NdP 5 O 14 , BiVO 4 , etc. 4,8,15,16 Moreover, the first complete ferroelastic strain-stress hysteresis loop (namely one of distinctive features of ferroelastic materials) was also observed in the metal oxide (Pb 3 (P 0.8 V 0.2 O 4 ) 2 ) in 1976. 17 More recently, with the increasing interest in flexible, wearable and intelligent responsive materials, organic molecular ferroelastics have been spotlighted due to their advantages of inherent flexibility, low cost, easy synthesis and biocompatibility, when compared to metal oxides.…”