Theoretical Study Of The Electronic Spectrum Property Of Organic Metal Complex With 2-(2-hydroxyphenyl) Pyridine Ligand

The study of organic electron luminescent material has been paid more and more widely attention recently. Most of researches concerning organic functional material indicate that organic ligand plays an important role in its complex.As significant electron transport material and emitting layer, the luminescent properties of Tris-8-hydroxyquinolate-aluminum and its ligand, 8-hydroxyquinolate, have been investigated in many works. 2-(2-hydroxy phenyl) pyridine (PP), similar to 8-hydroxyquinolate bond-linked of the same pyridine and phenol ring, has been paid widely attention in experiment and theory. Just for excited-state formation plays intrinsic role in organic light-emitting diode (OLED) devices, the excited state properties of PP may be of greater significance. The luminescent spectrum of PP has been measured in experiment. In theory, the methods of time-dependent density functional theory (TD-DFT) and single-excitation configuration interaction (CIS) with the hybrid B3LYP functional and the medium-sized polarized split-valence 6-31G(d) basis set were used to calculate spectrum properties of PP. TD-DFT calculation result predicts the absorption spectrum of PP in 324 nm (3.82eV), which is in very good agreement with experiment value 322 nm (3.85eV) determined in solvent chloroform. Considering the proton effect on the neutral system in different pH environment, two possible protonation states of PP were studied in theory in order to discuss the spectrum properties change rule in two possible protonation states of the chromophore.We optimize the geometry structure of organic metal complex BePP2in ground state with ah initio HF and TD-DFT method. On the basis of the optimized geometry structure, electronic spectrum of the excited state have been calculated in TD-DFT and CIS in order to discuss the relation between the electron transition mechanism and the spectrum properties. For considering the conjugate effect on spectrum property, we investigate electronic spectrum of the 8-liydroxyquinolate-beryllium (Beq2) and indicate the conjugate effect make the wavelength red shift.