Facile intra- and intermolecular charge transfer control for efficient mechanofluorochromic material

Abstract

A series of donor–acceptor–donor (D–A–D) pyrene (Py) 2,7-position-based compounds (CN, F, H, Me, and OMe) were designed and synthesized to demonstrate facile intra- and intermolecular charge transfer control by an...

Naphthalimide–Carbazole Compact Electron Donor–Acceptor Dyads: Effect of Molecular Geometry and Electron-Donating Capacity on the Spin-Orbit Charge Transfer Intersystem Crossing

“…Similar intermolecular electron transfer has been reported. 78,80 To prove this intermolecular process, the same ns-TA spectral experiments in solvents with high viscosity were carried out since high viscosity solvents will inhibit the molecular diffusion and slow down the intermolecular processes. In viscous solvent diethylene glycol (η = 30 mPa•s), the LE triplet state signal of NI was still observed as well as the NI −• signal with the rising process at 420 nm (Figure S31a,b).…”

Structure-controlled intramolecular charge transfer in asymmetric pyrene-based luminogens: synthesis, characterization and optical properties

“…29,30 Adjustable photophysical properties were displayed, which can be ascribed to the efficient intramolecular charge transfer. 31 However, mono-, or multi-symmetrical substitution patterns accounted for the vast majority among the current work reported on D-A pyrene derivatives. 19,23,32 Thus, the synthesis of asymmetrical D-A pyrene-based emitting materials is still a challenging task given the high symmetry of active-sites at the pyrene core.…”

“…The low-energy absorption band centered at 386-391 nm with equivalent intensity compared to the that mentioned above, may be ascribed to the ICT transition from the aryl ethynyl moiety to the pyrene core. 31 To verify these results, further investigation of the absorption behavior was performed in different solvents (see Fig. S9-S12 in the ESI †).…”

“…29,30 Adjustable photophysical properties were displayed, which can be ascribed to the efficient intramolecular charge transfer. 31…”

Substituent effects on the intermolecular interactions and emission behaviors in pyrene-based mechanochromic luminogens

“…This indicates an obvious electronic coupling in this donor-p-acceptor (D-p-A) system with an increase of electron-donors in the ground state. 40 Subsequently, the emission properties of both luminogens were recorded in diluted organic solvents of different polarities in which the difference in the emission phenomena was further magnified. As shown in Fig.…”