Transient Absorption Probe of Intermolecular Triplet Excimer of Naphthalene in Fluid Solutions:  Identification of the Species Based on Comparison to the Intramolecular Triplet Excimers of Covalently-Linked Dimers

Abstract

We report here the observation of the laser-induced transient absorption spectrum of intermolecular triplet excimers of naphthalene in fluid solution. This assignment is confirmed by comparison to the transient absorption spectra of the intramolecular triplet excimers of covalently linked dimers of naphthalene and quinoxaline.

Unexpected Nucleophilic Substitution Reaction of BODIPY: Preparation of the BODIPY–TEMPO Triad Showing Radical‐Enhanced Intersystem Crossing

“…Note that the molecular structures of DBT and BT are similar (the substitution profile of the BODIPY core), which leads us to propose that there exists a triplet excimer for DBT. The triplet excimers are known in co‐facial carbazole derivatives, naphthalene, and Pt II complexes,, but a BODIPY triplet excimer has not previously been reported. Moreover, the lifetime of the transient DBT species is 2.8 µs, which is substantially shorter than that of BT (27 µs).…”

Does phenazine form triplet excimer and dimer anion radical?

“…The results suggest that the 380 nm peak may be assigned to 3 (PZ) 2 * . Evidence for triplet excimer formation has been observed earlier in some cases [18][19][20][21][22]. Castro and Hochstrasser had first reported triplet excimers for halogenated benzenes from low temperature phosphorescence studies [18].…”

“…Castro and Hochstrasser had first reported triplet excimers for halogenated benzenes from low temperature phosphorescence studies [18]. Recently intermolecular triplet excimer of naphthalene has been observed in fluid solutions [22].…”

Tuning the colour and efficiency of OLEDs * *This chapter is dedicated to the memory of Professor Jan Kalinowski, who died on 18 December2010.

“…The square planar structures enable the Pt complex molecules to facially aggregate through attractive intermolecular interactions of Pt-Pt or ligand-ligand or a combination of these, facilitating formation of bi-molecular states in the ground state (dimers) or in the excited state (excimers). high singlet excimer effi ciency (∼75%), 15 though triplet excimer effi ciencies have long remained very low, 16,17 until recent reports on the high effi ciency PH and EPH from triplet excimers formed on heavy organometallic phosphor molecules. For example, red and near-infrared light-emitting devices (NIROLEDs) were demonstrated with external quantum effi ciencies of up to ϕ ext EL = 14.5% 18 when based on a neat fi lm of Pt L 2 Cl complex as triplet excimer emitter, showing photoluminescence (PL) effi ciency of ϕ PL (excimer) ≈ 35%.…”