Tuning the Solid-State Optical Properties of Tetracene Derivatives by Modification of the Alkyl Side-Chains: Crystallochromy and the Highest Fluorescence Quantum Yield in Acenes Larger than Anthracene
Melem tetramer, the newly synthesized carbon nitride compound is composed of oligomers with four melem units, is stable in air, and has improved optical properties compared to melon.
Due to the direct π - π interaction and excessive energy resonance transfer, it is very challenging to prepare CDs with high fluorescence quantum yield (QY) in solid state. In...
The solid state assembly of two cyclic hexapeptoids decorated respectively with five and six carbon N-alkyl side chains is analyzed by X-ray diffraction, intermolecular energies and lattice energy calculations.
AbstractIn this contribution, we investigate by means of correlated quantum-chemical calculations the influence of intermolecular interactions on the absorption and emission properties of conjugated chains. Various strategies are suggested to avoid a substantial decrease in fluorescence quantum yield in condensed media. Finally, the reliability of our theoretical approach is validated by showing the remarkable agreement obtained between the experimental data and the calculated optical properties of clusters formed by sexithienyl molecules.
Perylene dicarboximide dimer with electron withdrawing groups were synthesized and fully characterized by 1H-NMR and 13C-NMR spectra. The effects of the substituted groups on the optical and electrochemical properties of the two compounds were investigated. The ∏-∏* absorption peak of the perylene dicarboximide dimer compounds were red shifted from 525nm to 535nm. The band gaps of the dimer could be tuned from 2.28 eV to 2.13 eV. The first reduction wave of the dimer with electron withdrawing groups is shifted by 60 mV to more positive potential compared to that of perylene dicarboximide, suggesting the enhanced electron affinity. Furthemore, the dimer exhibited intermolecular aggregation, and decrease fluorescence quantum yield.
A water-stable In-MOF, constructed based on a conformationally-flexible tetraacid linker, i.e., 2,7-bis(3,5-dicarboxyphenyl)-9,9’-diphenyl-9H-fluorene, i.e., H4DPF, is shown to exhibit significantly enhanced solid-state fluorescence quantum yield (Φf) of 23% in comparison to...
A highly efficient deep red (DR) emitting organic solid based on a dicyano-phenylenevinylene derivative was reported. The structural and spectroscopic properties of the solid have been described in terms of crystallographic data and time dependent DFT analysis. A noteworthy fluorescence quantum yield of 53% was observed for the brightest emitter cast into solid films. This result can be explained in terms of aggregation-induced emission (AIE) effect.
The increased number of N-atoms induced a blueshift in absorption and a gain in fluorescence quantum yield, from 750 nm and ~0 % for pyrrole to 635 nm and ~40...
Synthesis of carbon nitride oligomer as a precursor of melon with improved fluorescence quantum yield