Giant Single-Crystal Shape Transformation with Wide Thermal Hysteresis Actuated by Synergistic Motions of Molecular Cations and Anions.

摘要: Manipulating the collective molecular movements to implement macroscopic mechanical response of bulk material is attractive and challenging. Here, an organic-inorganic hybrid single crystal synthesized, which exhibits a giant shape transformation with remarkable thermal hysteretic feature. The colossal anisotropic change, manifests as abrupt elongation ca. 9 % along crystallographic c-axis concomitant contraction in perpendicular direction, induced by significant reorientation imidazolium, accompanied substantial configurational variation CuBr42- complex anions. synergistic motions both cations anions engender large hysteresis (>30 K) crystal, implying that this may play role alternating memory media. Furthermore, due stable lattice, demonstrates naked-eye detectable was used actuator spontaneously control electric circuit temperature variation.