title: Iridium metal complexes as an unambiguous probe of intramolecular vibrational redistribution.
abstract: Ultrafast luminescence spectroscopy has been undertaken on three iridium cored phosphorescent complexes, with the Ir(ppy)3 molecule being compared with two Ir(ppy)3 cored dendrimers. Energy dissipation by intramolecular vibrational redistribution (IVR) and cooling shows as a luminescence decay because it decreases the admixture of singlet character to the emitting triplet state. A larger amount of vibrational energy dissipates by IVR in dendrimer complexes. We have therefore found a methodology of obtaining unambiguous information on the IVR process and show its potential to study IVR rates as a function of vibrational energy.
authors.affiliation: Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9SS, United Kingdom.
authors.forename: Gordon J
authors.initials: GJ
authors.lastname: Hedley
authors.forename: Arvydas
authors.initials: A
authors.lastname: Ruseckas
authors.forename: Zehua
authors.initials: Z
authors.lastname: Liu
authors.forename: Shih-Chun
authors.initials: SC
authors.lastname: Lo
authors.forename: Paul L
authors.initials: PL
authors.lastname: Burn
authors.forename: Ifor D W
authors.initials: ID
authors.lastname: Samuel
mesh_terms: D050091:Dendrimers / Q000737:chemistry*; D007495:Iridium / Q000737:chemistry*; D008163:Luminescent Measurements / Q000379:methods; D009942:Organometallic Compounds / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011758:Pyrroles / Q000737:chemistry
chemical_list: D050091:Dendrimers; D009942:Organometallic Compounds; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D007495:Iridium