Homoconjugation enhances the photophysical and electrochemical properties of a new 3D intramolecular charge transfer iptycene displaying deep blue emission

Abstract

Greater than the sum of its parts – a 3D ICT molecule displays greatly improved optoelectronic properties over a 2D analogue.

Conformational Dependence of Triplet Energies in Rotationally Hindered N‐ and S‐Heterocyclic Dimers: New Design and Measurement Rules for High Triplet Energy OLED Host Materials

“…This gives carbazole and its derivatives optical and electronic properties well suited for use in emissive devices based upon organic molecules. Carbazole has great synthetic versatility permitting systematic variations through substitution, interconversion and coupling reactions, allowing optimisation of the optoelectronic properties of carbazole derivatives for many applications [1–11] . Among the most important of these applications are their use as hole transport materials (HTMs), [12] or as host materials in the emissive layer (EML) of organic light emitting diodes (OLEDs) [13–17] .…”

Comparing the microstructure and photovoltaic performance of 3 perylene imide acceptors with similar energy levels but different packing tendencies

“…The absence of the triptycene contribution to the frontier molecular orbitals precludes the homoconjugation effect already observed in other iptycene derivatives. 31,32 For 4PIPM, a similar scenario is found, where the tetraphenylmethane core minimally contributes to the frontier molecular orbitals. To gain some insight into the electrochemical and optical properties of the three NFAs, they were characterized by cyclic voltammetry and UV-Visible and fluorescence spectroscopies.…”

Simultaneous enhancement of thermally activated delayed fluorescence and photoluminescence quantum yield via homoconjugation

“…Such an enhancement of ICT through homoconjugation has only been noted once previously, in a structure that does not display TADF. 41 Notably, S1 is also significantly more stabilised than T1 upon trimerization of compound 1 to 2, suggesting the iptycene core can be employed to fine-tune the ΔEST of TADF compounds. The TADF parameters of 1 and 2 were evaluated in toluene solution (Figure 4).…”

“…[38][39][40] Recently, we extended this phenomenon to ICT transitions. 41 Upon trimerization of a fluorescent luminophore through a homoconjugated iptycene core, large enhancements in ICT parameters such as ɛ, kr, and PLQY (i.e. radiative transitions) were observed.…”