Premium
Graphical Abstract: Eur. J. Inorg. Chem. 21/2011
Publication year - 2011
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201190062
Subject(s) - photon upconversion , chemistry , photoexcitation , phosphorescence , quantum yield , photochemistry , excited state , spectroscopy , triplet state , ultrafast laser spectroscopy , oled , fluorescence , atomic physics , molecule , organic chemistry , ion , physics , quantum mechanics , layer (electronics)
The cover picture shows the triplet‐triplet‐annihilation (TTA) upconversion between a visible‐light harvesting Ir III complex and 9,10‐diphenylanthracene (DPA). In the upper left‐hand corner is the qualitative Jablonski diagram describing the photophysical process involved in the TTA upconversion. Although the coumarin‐containing Ir III complexes are weakly phosphorescent, we proved that the long‐lived 3 IL excited state was populated upon photoexcitation by using time‐resolved transient absorption spectroscopy, emission spectroscopy at 77 K, and DFT calculations. The complexes were used as triplet sensitizers for TTA upconversion, and an upconversion quantum yield of up to 23.4 ° was observed. Thus, we propose that the T1 excited state of the triplet sensitizers does not necessarily have to be emissive. Details are discussed in the article by J. Zhao et al. on p. 3165 ff. The cover art was produced by Dr. Xin Liu (Dalian University of Technology).