Heteroatoms Tuning And Molecular Conformation Controlling On Optoelectronic Properties Of Organic Conjugated Polymers: Theoretical And Experimental Studies

Organic conjugated polymers have indicated the extensive potentials in optoelectronic materials, such as organic light-emitting diodes(OLED), organic solar cell(OSC), organic filed effect transistor(OFET) et al. applications due to their very good properties in processing, spectra tuning and other characters better than small molecules. For better understanding the optical and physical properties of heterofluorene-based organic materials, a series of conjugated small, oligmer and polymers have been investigated by theoretical methods on their electronic structures, optoelectronic characters and the relationships between molecular structure and properties. In this work, the DFT and MD quantum calculation methods have been used to optimize the different target conjugated polymers based on the classic theoretical functionals and models, around molecular design and optoelectronic process, to investigate the structure and conformation of polymers in order to better understand the relationships between the structure and properties,as well as the optoelectronic mechanism. To clarify the impacts of hetero-atoms on molecular conjugation length and orbital interactions, structure sequence, substitutes, solvation effects factors have been discussed, provided worthy predictions and guidance for reasonal design of conjugated materials with high optoelectronic performance, and obtained the important results:(1) The hetero-atoms incorptions and conformation control can tuning the optoelectronic properties of conjugated polymers effectively found in the design a series of new class of organic conjugated polymers/oligomers.(2) The influence of molacular structure sequence, substitutes, solvation effects on the electronic and optophysical properties have been investigated to realize the reasonal control the performace. The good results have been obtained since the theoretical predictions are consistent with experimental meaturements.(3) First report the different luminescence properties of chiral conjugated polymers and propose the mechanism by DFT and MD theoretical quantum simulations.(4) First report the ultralong luminescent phenomenon of pure organic materials and investigate the possible mechanism, provided with better understanding of the tuning strategy for molecular excited states.