Investigation on Photophysical Properties of D-π-A-π-D-Type Fluorenone-Based Linear Conjugated Oligomers by Using Femtosecond Transient Absorption Spectroscopy.

The effects of π-spacer and electron donor groups on the photophysical behaviors of fluorenone-based linear conjugated oligomers have been systemically investigated. Solvent-dependent steady-state measurements exhibit that the fluorene vinylene (FV) spacer and the electron-donating ability of donor group are able to modulate the spectral features of oligomers and the fluorescence quantum yield could decrease with the increasing of the solvent polarity. Meanwhile, quantum chemical calculation simulates their absorption spectra, and analyzes their electron transition components simultaneously.