| 초록 |
The self-assembling coordination polymers based on Pd(II), Cu(II) and Ag(I) metal ions were prepared from complexation of a bent-shaped bispyridine ligand and a corresponding transition metal. The polymer based on Pd(II) self-assembles into layer structure formed by bridging bispyridine ligands connected in a trans position of the square planar coordination geometry of metal center. In contrast, the polymer based on Cu(II) adopts double helical conformations with regular grooves, driven by interstranded copper-chloride dimeric interaction. Furthermore, the coordination polymer based on Ag(I) ion self-assembles into a helical structure that displays reversible extension-contraction motions, triggered by temperature. It is also notable that this dynamic conformational change leads to a fluorescence switching between the fluorescent stretched and non-fluorescent compressed states of the supramolecular springs. |
