Transient process in the triplet states of phosphorescent Ir(ppy)3 material dope

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