Direct observation of intersystem crossing in a thermally activated delayed fluorescence copper complex in the solid state

Larissa Bergmann, Gordon James Hedley, Thomas Baumann, Stefan Braese, Ifor David William Samuel

Research output: Contribution to journalArticlepeer-review

135 Citations (Scopus)
9 Downloads (Pure)

Abstract

Intersystem crossing in thermally activated delayed fluorescence (TADF) materials is an important process that controls the rate at which singlet states convert to triplets; however, measuring this directly in TADF materials is difficult. TADF is a significant emerging technology that enables the harvesting of triplets as well as singlet excited states for emission in organic light emitting diodes. We have observed the picosecond time-resolved photoluminescence of a highly luminescent, neutral copper(I) complex in the solid state that shows TADF. The time constant of intersystem crossing is measured to be 27 picoseconds. Subsequent overall reverse intersystem crossing is slow, leading to population equilibration and TADF with an average lifetime of 11.5 microseconds. These first measurements of intersystem crossing in the solid state in this class of mononuclear copper(I) complexes give a better understanding of the excited-state processes and mechanisms that ensure efficient TADF.
Original languageEnglish
Article numbere1500889
Number of pages7
JournalScience Advances
Volume2
Issue number1
DOIs
Publication statusPublished - 1 Jan 2016

Keywords

  • Thermally-activated delayed fluorescence
  • Organic light-emitting diode
  • Copper complex
  • Intersystem crossing
  • Time-resolved photoluminescence

Fingerprint

Dive into the research topics of 'Direct observation of intersystem crossing in a thermally activated delayed fluorescence copper complex in the solid state'. Together they form a unique fingerprint.

Cite this