Mechanofluorochromism of NIR-emitting dyes based on difluoroboron β-carbonyl cyclic ketonate complexes

Multi Stimuli Responsive Non‐Doped Red Emitting AIEE Active Phenothiazine‐Based Chalcones: Crystal Structure, Solvatochromism, Turn‐on Mechanofluorochromism and Acidochromism

“…Despite having a centrosymmetric space group C2/c and lesser intermolecular interaction in the crystal lattice, C4 still managed to show mechanofluorochromism [96–99] . The red shifts observed in the emission maxima upon grinding the as‐synthesized semi‐crystalline solid samples (Figure 9) suggest that the plausible changes in twist angle and intermolecular or intramolecular interactions in the crystal lattice of C4 (Figure S11b) may lead to planarization under mechanical stress, which reduces non‐radiative relaxations and causes red‐shifted turn‐on emission [46,100,101] . Fuming and annealing of ground samples of C2 and C3 helped in regaining the diffraction peaks to some extent only (Figure S23).…”

“…[96][97][98][99] The red shifts observed in the emission maxima upon grinding the as-synthesized semicrystalline solid samples (Figure 9) suggest that the plausible changes in twist angle and intermolecular or intramolecular interactions in the crystal lattice of C4 (Figure S11b) may lead to planarization under mechanical stress, which reduces nonradiative relaxations and causes red-shifted turn-on emission. [46,100,101] Fuming and annealing of ground samples of C2 and C3 helped in regaining the diffraction peaks to some extent only (Figure S23). The amorphous nature of the ground powder of the chalcones is one of the outstanding and uncommon features for a red fluorescent organic material and thus an excellent candidate for the fabrication of OLEDs.…”

Solvent‐dependent ultrafast optical response of conjugated push–pull chromophores

“…These materials were obtained from the research group of Professor Lu Ran of the College of Chemistry of Jilin University, and were not further processed. We dissolved the two compounds at 2 × 10 −5 M in THF and dimethyl sulfoxide (DMSO), respectively.…”

Unsymmetrical boron diketonates containing strong electron-donating groups as mechanochromic fluorescent solids

“…24,25 In addition, solid state luminescence studies showed that many BDK compounds present mechanochromic properties, their emission wavelength being correlated to their solid structure. [26][27][28][29][30][31][32][33][34][35][36][37] BDK compounds, in solid state, were also applied for the detection of volatile amines because these latter can interact with difluoroboron moiety, lowering their acceptor character, leading to blue shifted emission and increase of fluorescence quantum yields. [38][39][40] The development of synthetic methods producing unsymmetrical β-diketone compounds can give access to push pull chromophores i.e.…”