One-Dimensional Organic-Inorganic Hybrid Perovskite With Shear Strain.

Room-temperature multiresponsive materials have excellent environmental adaptability due to their integration of multichannel physical response capabilities and the ability to undergo phase transitions under near room temperature conditions, providing unique advantages for the development of smart devices. However, these materials still face challenges in terms of design, stability, and manufacturability. Hybrid metal halides have become highly regarded candidates for materials due to their potential. This study synthesized (R/S-2-HMD)PbBr3 (R/S-2-HMD = (R/S)-2-hydroxymethyl-1-methylpyrrolidinium cation), which can switch on and off four physical properties, including enthalpy, dielectric constant, photoluminescence intensity, and nonlinear optical response near room temperature, accompanied by significant macroscopic deformation. This change is due to the synergistic effect of ordered-disorder and displacement-type phase transition, causing the crystal to undergo shear deformation in the form of crystal plane slip, with a shear strain value of about 6.60%. Because of the phase transition temperature being close to room temperature, the heat generated by infrared light irradiation can induce this shape change.