TY - JOUR A1 - Nag, Sayak A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Ghosh, Soumyajit T1 - Stress and Light-Induced Dual Mechanical Properties of Two 1,3-Dicyanostilbene Derivative Crystals N2 - Dynamic molecular crystals with multistimuli responses hold immense potential for applications as actuators and smart materials. Here, we report two new 1,3-dicyanostilbene derivative crystals (crystals 1 and 2), which exhibit dual mechanical responses. Both crystals 1 and 2 demonstrate stress-induced mechanical flexibility and light-induced photomechanical bending upon exposure to a 375 nm UV LED. These two distinct mechanical responses are associated with different underlying phenomena and are independent of each other. Mechanical flexibility is attributed to the absence of slip planes and a criss-cross packing arrangement in an isotropic structure, while photomechanical bending is ascribed to the formation of a heterogeneous phase distribution due to Z → E photoisomerization. However, they show thermal reversibility, pointing toward a reversible E → Z back isomerization. This study demonstrates that single molecular crystals combining mechanical flexibility and photomechanical bending can be designed and fabricated for developing multistimuli responsive actuators. KW - Photoisomerization KW - Crystal structure KW - Crystals KW - Flexibility KW - Molecules PY - 2025 DO - https://doi.org/10.1021/acs.cgd.5c00097 SN - 1528-7483 SP - 1 EP - 11 PB - American Chemical Society (ACS) AN - OPUS4-63267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -