The geometric structures of 10-hydroxybenzo[h]quinoline lithium(LiBQ) complex in the ground-state(S0) and the lowest singlet excited-state(S1) were optimized by B3LYP and ab initio CIS methods at 6-31G(d,p) level respectively.The absorption and emission spectra of the complex were investigated by the time dependent density functional theory(TD-DFT) level with PCM model on the basis of the optimized ground and excited states geometry respectively.The calculated lowest-lying absorption of the complex was attributed to intraligand charge transfer(ILCT) transitions mainly.The calculated emission of the complex can be described as originated from an excited state with intraligand charge transfer(ILCT) character mainly.The result displayed that the complex was a potential electroluminescent material with blue light emission.

Three new D-π-A type compounds, each containing one benzothiazole ring as an electron acceptor and one N-ethylcarbazole group as electron donor, were synthesized and characterized by elemental analysis, NMR, MS and thermogravimetric analysis. The absorption and emission spectra of three compounds were experimentally determined in several solvents and were simultaneously computed using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The calculated reorganization energy for hole and electron indicates that three compounds are in favor of hole transport than electron transport. The calculated absorption and emission wavelengths are well coincident with the measured data. The calculated lowest-lying absorption spectra can be mainly attributed to intramolecular charge transfer (ICT). And the calculated fluorescence spectra can be mainly described as originating from an excited state with intramolecular charge transfer (ICT) character. The results show that three compounds exhibited excellent thermal stability and high fluorescence quantum yields, indicating their potential applications as excellent optoelectronic material in optical field.

The geometric structures of 10-hydroxybenzo[h]quinoline zinc [Zn(BQ)2] complex and its derivatives substituted by cyano-groups in the ground state and the lowest singlet excited state were optimized by B3LYP and ab initio CIS methods at LanL2DZ level, respectively. The absorption and emission spectra of these complexes were investigated by the time-dependent density functional theory (TD-DFT) level with PCM model on the basis of the optimized ground and excited states geometries, respectively. The calculated lowest-lying absorptions of all complexes were attributed to ILCT transitions mainly. The calculated emissions of complexes can be described as originated from an excited state with ILCT character mainly. The calculated results showed that the absorption and emission maximums could be tuned by changing the site of the substitutions. The Zn(BQ)2 and its derivatives substituted by cyano-groups were potential electroluminescent materials with blue, green and yellow light emission.

A novel intramolecular donor–acceptor compound has been synthesized and characterized. This compound was a symmetrical A–π–D–π–A type molecule containing two benzimidazole rings as two electron acceptors (A) and an N-ethylcarbazole group as electron donors (D). The absorption and emission spectra of the compound were determined by experimental methods in solution and were computed by using the density functional theory (DFT) and the time-dependent density functional theory (TDDFT) in gas phase and in chloroform solution. The calculated absorption and emission wavelengths were in good agreement with the experimental ones. The fluorescence quantum yields and fluorescence lifetimes of the compound in several solvents have been studied by means of steady state and time resolved fluorescence. The results showed the compound had high quantum yield. The cross-section of two-photon absorption (TPA) of the compound was measured by using femtosecond laser in dichloromethane solution. The result indicated the cross-section maximum of two-photon absorption was 430 GM at 600 nm. These results made the compound of great interest as a new fluorescent probe and photoluminescence material.

N-ethyl-3,6-Bisbenzoxazolyl was synthesized from carbazole and 2-Aminophenol.The structure was confirmed by 1H NMR,13C NMR and IR.The optical properties of this compound was systematically studied by UV-Vis absorption and fluorescence spectra.The results showed that this compound might be used as a blue emission material.