Osmium‐ and Ruthenium‐Based Phosphorescent Materials: Design, Photophysics, and Utilization in OLED Fabrication

Osmium(II) complexes possessing β-diketonate, quinolinate, diimine, and C-linked pyridyl azolate chelates reveal interesting structural and photophysical properties. Spectroscopic and dynamic measurements, in combination with theoretical analyses, have provided an important understanding of the electronically excited state properties of these complexes, such as the energy gap and nature of the lower lying states, rate for intersystem crossing, and the efficiency of corresponding radiative decay and nonradiative deactivation processes. This review also reports on the synthetic processes

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