The reasons for ligand-dependent quantum yields and spectroscopic properties of platinum(II) complexes based on tetradentate O^N^C^N ligands: a DFT and TD-DFT study

摘要: DFT and TD-DFT methods have been employed to theoretically investigate the properties of three recently synthesized green-emitting platinum(II) complexes (1-3) bearing tetradentate (ONCN)-N-boolean AND-C-boolean AND-N-boolean AND ligands ((OCNC)-C-boolean = 2-(4-(3,5-di-tert-butylphenyl)-6-(3-(pyridin-2-yl) phenyl)-pyridin-2-yl) phenolate its derivatives) that testified be good emitters in organic light-emitting diodes (OLEDs), especially for complex 3. The effect variation substituents on electronic optical is emphatically explored. Our calculation results reveal introduction an electron-releasing group one phenyl ring (OCNC)-C-boolean ligand (complex 2) does not result a distinct alteration spectra. However, incorporation norbornane 3) leads blue-shift absorption emission spectra as compared with 1. In addition, how are affected by solvent polarity studied. Both display red-shifts various degrees decrease polarity. different phosphorescent quantum yields compared. It reasonable believe high (MLCT)-M-3 (metal-to-ligand charge transfer) contribution percentage metallic character (M-c, %) process, well largest vertical transition energy 3, highest efficiency.