Organic room-temperature phosphorescence from halogen-bonded organic frameworks: hidden electronic effects in rigidified chromophores

Abstract

Development of purely organic materials displaying room-temperature phosphorescence (RTP) will expand the toolbox of inorganic phosphors for imaging, sensing or display applications. While molecular solids were found to suppress non-radiative...

Recent advances in room temperature phosphorescence of crystalline boron containing organic compounds

“…[38] The halogenated derivatives 9g-9j showed a progressive decrease in their phosphorescence lifetimes with increasing atomic number, with the shortest τ P (and the brightest emission) observed for the brominated 9h. This trend, also seen in other halogenbonded RTP solids, [39,40] is a result of two factors: first, increased spin-orbit coupling accelerates the ISC and the phosphorescence rate; second, the steric bulk of larger atoms may lead to looser packing and increase the rate of nonradiative relaxation.…”

Halogen bonding regulated functional nanomaterials

“… 113 Recently, a range of fast triplet-forming tetraethyl naphthalene-1,4,5,8-tetracarboxylates were developed for XB-based RTP by Wu and coworkers. 114 The number and position of bromo substituents of the compound were controlled to adjust the intermolecular XB interaction, to realize the suppression of non-radiative relaxation and improvement of the ISC process. The highest QE of 20% was obtained when the molecule is surrounded by a Br⋯O halogen-bonded network.…”

Halide-containing organic persistent luminescent materials for environmental sensing applications

“…Internal and external heavy-atom effects promote the ISC (or RISC) process and radiative transitions from triplet excited states to ground states, leading to distinct OPL intensity and lifetimes for halogen substituted compounds with different SOC constants. 7,8,29,40–44 It brings great convenience to the OPL molecular design for different environmental sensing application. Generally, iodine-containing OPL materials exhibit high phosphorescence quantum yields with short lifetimes of about several milliseconds, while long emission lifetimes of about hundreds of milliseconds will be realized in chlorine substituted OPL derivatives.…”