Organic fluorophores are extensively utilized in the second near-infrared window (NIR-II) for bioimaging applications, owing to their superior biocompatibility and favorable metabolic properties. This study focused on the shielding unit-donor-acceptor-donor-shielding unit (S-D-A-D-S) architecture of organic π-conjugated molecules, which mitigates aggregation-induced quenching by the modification of terminal shielding units. The introduction of thiophene groups as donor units serves to augment conjugation length, thereby inducing a redshift in the fluorescence wavelength with an increasing number of donor units. Density functional theory (DFT) and time-dependent DFT (TD-DFT) methods were employed to investigate the frontier molecular orbitals, electronic absorption, and fluorescence spectra of the designed compounds. An in-depth analysis elucidates the fluorescence mechanisms and the impact of shielding units on the fluorescence properties of the compounds. The results indicate that the phenoxazine group (POZ) linked at position 'a' provides the most pronounced shielding effect. Extending the conjugation in the POZ-a compound results in an extend fluorescence wavelength within the NIR-II spectrum, with the POZ-5 compound achieving a fluorescence wavelength of up to 1308 nm in aqueous environment. Furthermore, modulating the π-conjugated bridge's length enables precise control over the compound's fluorescence wavelength, luminescence intensity and color purity, with negligible impact from the shielding units on the compound's fluorescence performance.
In this paper,we synthesized the luminescence materal of in MB 6O 10 host by spread methods of high temperature and solid were discussed.M=Mg、Ca、Sr、Ba、Zn、Cd;One and both prode into Pb 2+ 、Sn 2+ 、Mn 2+ 、Bi 3+ 、Ce 3+ 、Tb 3+ 、Eu 2+ 、Sm 2+ 、Dy 3+ etc.The effect of sensitization and host in MB 6O 10 were also discussed in the air.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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