Red shift of green-emission band has been observed for fac tris(2-phenylpyridine) iridium (Ir(ppy)3) doped in polycarbonate at 8 K during time evolution after 355-nm laser of 1-ns pulse width. We explain the peak shift and vibronic structure of the emission band using the Franck-Condon principle and the model of (1) three zero-field splitting substates of the triplet state, (2) relaxation processes among the three substates, and (3) different Huang-Rhys factors for these substates. Good agreement was obtained between the calculated and measured emission spectra at various delay times.
© 2005 Chinese Optics Letters
(160.2540) Materials : Fluorescent and luminescent materials
(160.4760) Materials : Optical properties
(160.4890) Materials : Organic materials
(300.6500) Spectroscopy : Spectroscopy, time-resolved
(310.6860) Thin films : Thin films, optical properties
Nadeer Aljaroudi and Taiju Tsuboi, "Transient process in the triplet states of phosphorescent Ir(ppy)3 material doped in organic materials: peak shift of the emission band in polycarbonate," Chin. Opt. Lett. 3, S41-S43 (2005)