| Popis: |
Novel diphenylphenanthrenes (DPPs) were prepared by a photocyclization method, and the substituent effects of the phenyl groups on the photophysical properties of the phenanthrene chromophore were investigated based on measurements of fluorescence yields, lifetimes, and transient absorption. Fluorescence activities in DPPs are increased by introducing phenyl rings that can enhance the transition moment along the short axis of the phenanthrene skeleton. Intersystem crossing from the fluorescent states to the triplet manifolds is shown to be operative through the triplet-triplet absorption spectra obtained by laser photolysis techniques. preparations. In the present work, we are successfully prepared a variety of diphenylphenanthrenes (DPPs, Chart 1) using the Mallory Some aromatic molecules with extended π systems can be divided into two major groups from the molecular shapes. One is acenes representative of anthracene, tetracene and pentacene having linearly aligned benzene rings. In these two decades, acenes have been paid attention due to the potentials for organic semiconductor such as active layers of organic field effect transistors (OFET) |
