在平板显示和固态照明等领域有机电致发光器件有广阔的应用前景。相对于红色和绿色磷光材料,蓝色电致磷光材料较为匮乏。为了寻求蓝色电致磷光材料,采用密度泛函理论研究了四个环金属化Ir(Ⅲ)配合物的几何结构、吸收光谱和磷光光谱性质。由计算结果可知,所得最低能量吸收波长与发射波长都与实验测量的数据非常相近。四个配合物最低能量吸收分别位于364、357、361和350nm处,主要来源于HOMO→LUMO跃迁。四个配合物的发射波长分别在463、480、490和494nm处,均来自于激发组态LUMO→HOMO的贡献。
It has a wide application prospect in flat panel display and solid-state illumination.Compared with red and green phosphorescent materials,the research progress of blue phosphorescent materials are scarce.In order to find blue phosphorescent materials,the geometric structure,absorption spectra and phosphorescent properties of four ring metallized Ir(Ⅲ) complexes were studied by density functional theory.It can be seen from the calculation results that the minimum energy absorption wavelength and emission wavelength were very close to the experimental data.The lowest energy absorption of the four complexes was at 364,357,361 and 350nm respectively,which mainly came from the HOMO→LUMO transition.The emission wavelength of the four complexes were at 463,480,490 and 494nm respectively,all of which came from the contribution of excitation configuration LUMO→HOMO.
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基金资助
吉林省教育厅“十三五”科学技术项目(JJKH20181021KJ)
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