Theoretical Study Of Functional Integration Of Donor/Acceptor Blocks In Organic Optoelectronic Materials

Organic optoelectronic materials with D （Donor）-A （Acceptor） structure have been wide lyused for the applications of fluorescent sensors, phosphorescent organic light-emitting diodes（PhOLEDs）, organic photovoltaic cells （OPV） and so on. The molecular structures, electronicstructures, triplet energies, absorption spectras, and reorgnization energies of the Hg²⁺fluorescent sensor materials, blue PhOLED host materials and OPV materials were theoreticallyinvestigated via de ns ity functional theory （DFT） calculations to provide deep understandings andguidelines for the molecular design. It was found that in heterocyclic Hg²⁺receptors （acceptors）,the most stable binding site for Hg²⁺is N atom instead of S atom, although the S atom may bekinetically favored based on geometry, NBO charge, liga nd-to-metal charge transfer, andquadratic differences in group softness analysis. NTD, QL, BTP, TPD, and MPD are excellentHg²⁺receptors for their high binding energy and high interaction energy. The HOMO/LUMOlevel, HOMO–LUMO band gap and triplet energy of host materials can be effectively tuned bythe different side groups （donors/acceptors） and linking topologies. Linking a hole-transportinggroup and an electron-transpor ting group （especially carbazole and diphenyl-phosphine oxide） tothe meta-position of π-conjugated cores is an effective strategy for the design ofhigh-performance bipolar host materials. Si-containing Benzo[c][1,2,5]thiadiazole derivativesare good acceptors of OPV materials because of the good molecular structures, the low LUMOlevel and the large absorption width. These results are valuable for the design and developmentof new organic optoelectronic materials with D-A structure.