Theoretical Study On Photoinduced Intramolecular Charge Transfer Mechanisms Of Aromatic Conjugated Systems

Organic conjugated molecules consisting of electron-donor and electron-acceptor groups have potential applications in nonlinear optical materials and molecular devices due to their remarkable photophysical and electro-optical properties. The photoinduced intramolecular charge transfer (ICT) as a fundamental process is involved in photophysics of the excited state. The detailed understanding of excited-state properties and ICT mechanisms of such donor-acceptor systems is important to facilitate design of molecular materials. In this dissertation, plausible photoinduced ICT mechanisms of selected aromatic conjugated systems have been investigated systemically by density functional theory and sophisticated ab initial methodologies. The dissertation is composed of three parts: The first part is the first chapter, where the theoretical basis of electron transfer, the status of research, the controversy about ICT have been introduced; in the second part, we focused on introduction of quantum-chemistry methodologies for the excited state relative to our work; the third part is the most important part of this dissertation, where we have explored photoinduced ICT mechanisms and corresponding photophysics and photochemistry of some representative aromatic conjugated molecules on the basis of their excited-states and photophysical properties.Target systems and concluding remarks in the present study can be summarized as follows:1. DMABN. Low-lying singlet and triplet states of 4-dimethylamino-...