The author of 《Realization of Highly Efficient Red Phosphorescence from Bis-Tridentate Iridium(III) Phosphors》 were Gnanasekaran, Premkumar; Yuan, Yi; Lee, Chun-Sing; Zhou, Xiuwen; Jen, Alex K.-Y.; Chi, Yun. And the article was published in Inorganic Chemistry in 2019. Formula: C5H3Br2N The author mentioned the following in the article:
Bis-tridentate Ir(III) metal complexes bring forth interesting photophys. properties, among which the orthogonal arranged, planar tridentate chelates could increase the emission efficiency due to the greater rigidity and, in the meantime, allow strong interligand stacking that could deteriorate the emission efficiency. The authors bypassed this hurdle by design of 5 bis-tridentate Ir(III) complexes (1-5), to which both of their monoanionic ancillary and dianionic chromophoric chelate were functionalized derivative of 2-pyrazolyl-6-phenylpyridine, i.e. pzpyphH2 parent chelate. Hence, addition of Ph substituent to the pyrazolyl fragment of pzpyphH2 gave rise to the precursors of monoanionic chelate (A1H-A3H), on which the addnl. CMe3 and/or methoxy groups were introduced at the selected positions for tuning their steric and electronic properties, while precursors of dianionic chelates was judiciously prepared with an isoquniolinyl central unit on pziqphH2 in giving the red shifted emission (cf. L1H2 and L2H2). Factors affected their photophys. properties were discussed by theor. methods based on DFT and TD-DFT calculation, confirming that the T1 excited state of all studied Ir(III) complexes shows a mixed metal-to-ligand charge transfer (MLCT), intraligand charge transfer (ILCT), ligand-to-ligand charge transfer (LLCT), and ligand-centered (LC) transition character. But the poor quantum yield of 3 is due to the facilitation of the nonradiative decay in comparison to the radiative process. As for potential OLED applications, Ir(III) complex 2 gives superior performance with maximum efficiencies of 28.17%, 41.25 cd A-1 and 37.03 lm W-1, CIEx,y = 0.63, 0.37 at 50 mA cm-2, and small efficiency roll-off. Crystallog. data are given. In the part of experimental materials, we found many familiar compounds, such as 2,6-Dibromopyridine(cas: 626-05-1Formula: C5H3Br2N)
2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. Pyridine is a relatively complex molecule and exhibits a number of different bands in IR spectra. Among others, the bands characterizing the ν8a and ν19b modes have been found to be sensitive to the coordination or protonation of the molecule. Note that the band that is diagnostic for the PyH+ ion at about 1545 cm− 1 (ν19b mode) does not overlap with any of the other bands.Formula: C5H3Br2N