| dc.description.abstract | In recent years, emission materials are especially interesting because the wide range of applications in advanced technologies such as molecular recognition, fluorescence probes, microscopy imaging, and organic light-emitting diodes (OLEDs). Liquid crystals are also interest in research, because its properties of orientational ordering and molecular self-organization. These materials provided charge carrier mobility to improve device performance. Therefore, exploiting the luminesecent mesogens actract lots of discussion.
In this work, five-membered heterocyclic ring derivatives 2a-b, 4a-c and their borondifluoride complexes 1a-BF2, 1b-BF2, 2a-BF2, 2b-BF2 and coper complexes 1a-Cu, 1b-Cu, 2a-Cu, 2b-Cu were prepared and investigated. All compounds were characterized by 1H and 13C NMR spectroscopes, elementary analysis. Their mesomorphic behavior was studied by polarized optical microscope, differential scanning calorimeter and X-ray diffraction. All compounds exhibited liquid crystal phases except borondifluoride complexes. Futhermore, compounds 2a-b, 4a-c with five-membered heterocyclic ring and naphthalene have wider mesophases, owing to the increasing of structure asymmetry and intermoluce interaction. Optical property was investigated by UV/Vis and photoluminescence spectroscopy. Because of the donor-acceptor effect, their BF2 complexes have emissions of near-infrared wavelengths. | en_US |