Material profiling for photocrystallography: Relating single-crystal photophysical and structural properties of luminescent bis-cyclometalated iridium-based complexes

Jacqueline M. Cole*, Katharine F. Bowes, Ian P. Clark, Kian Sing Low, Anita Zeidler, Anthony W. Parker, Inamur R. Laskar, Teng-Ming Chen

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

9 Scopus citations

Abstract

The photophysical properties of seven luminescent iridium complexes are characterized in their single-crystal form, and the photoactivity is related to their molecular structures. Specifically, solid-state optical emission spectra and associated lifetimes are determined from single crystals of iridium complexes containing three bidentate ligands: two variously substituted 2-phenylbenzothiazoles and either a 2,4-pentadione (acetylacetone) or 2-pyridinecarboxylic (picolinic) acid. All complexes studied exhibit emissive behavior in the solid-state which originates from 3π-π* and metal-to-ligand-charge-transfer (MLCT) electronic transitions; this is supported by density functional theory. Phosphorescence is observed in all cases with microsecond lifetimes, ranging from 0.30 to 2.4 μs at 298 K and 1.4-4.0 μs at 100 K. Structure-property relationships are established which are relevant to the potential solid-state application of this series of luminescent complexes as organic light emitting diodes (OLED) material components. In addition, these materials are assessed for their suitability to time-resolved pump-probe photocrystallography experiments, which will reveal their photoexcited state structure. Accordingly, the design process by which materials are selected and technical parameters are defined for a photocrystallography experiment is illustrated. This family of complexes presents a case study for this photocrystallography material profiling. Results show that the time-resolved photoexcited state structure, featuring the MLCT transition is, in principle at least, viable for two of these complexes.

Original languageEnglish
Pages (from-to)1826-1837
Number of pages12
JournalCrystal Growth and Design
Volume13
Issue number5
DOIs
StatePublished - 1 May 2013

Fingerprint Dive into the research topics of 'Material profiling for photocrystallography: Relating single-crystal photophysical and structural properties of luminescent bis-cyclometalated iridium-based complexes'. Together they form a unique fingerprint.

Cite this