Properties Of Organic Radical Materials:Stimuli-responsive Of Phosphorescence&Magnetic Properties

This thesis reviewed the advancement of near-infrared absorbing organic materials, stimuli-responsive magnetic organic materials and stimuli-responsive luminescence organic materials. On the near-infrared absorbing organic materials, we synthesized a couple of near-infrared absorption organic radicals based on Hfbipo-·(1and2); then, we found that molecular1and2and their hydrochloride1·(HC1)n and2·(HCl)n exhibit stimuli-responsive magnetic and luminescence properties; besides, we reported two new supramolecular materials based on β-cyclodextrin inclusion complex samples with partially included organic radicals1@CD and2@CD, and discovered1@CD exhibits light-driven reversibly photoswitchable behavior.Near-infrared absorbing materials have been used in many fileds, such as conversion of solar energy to electrical energy, optical communications, bioimaging, and biosensors etc. And organic radical material is one of the most important components of them. We have synthesis a couple of NIR absorbing organic radicals1and2. From the single crystal X-ray diffraction, we know that compound1forms a1D chain structure, and the dimeric2also form a1D chain structure. This kind of stacking mode make them have extended π-conjugated systems, thus helps them exthibt NIR absorbing properties.Variations or perturbations in the chemical structure or molecular packing mode via response to external stimuli usually induce interesting spectroscopic and luminescent changes for organic materials. Because the conversion of molecular structures in the solid state is very difficult, the design and synthesis of organic materials that reveal efficient and reversible switching behavors in the solid state still remain a challenge. We obtained a couple of organic meterials la and2a based on compounds1and2. We found compounds la and2a are very easy deprotonation in solution, so we further investigate their ability to sense acid-base vapors. And the results are interesting, both exthibt acid-base vapors stimuli-responsive switching of magnetic properties and solid-state colors. In addition, we found both1@CD and2@CD show significant fluorescence enhancement phenomenon, and both exhibit light-driven reversibly photoswitchable behavior. This kind of properties has potential applications in many fields.