Xanthene

About: Xanthene is a research topic. Over the lifetime, 2132 publications have been published within this topic receiving 34803 citations. The topic is also known as: Xanthene & dibenzo[a,e]pyran.

Spirofluorene xanthene phosphine oxide electro-phosphorescent main materials and synthesis and application methods thereof

Abstract: The invention relates to spirofluorene xanthene phosphine oxide electro-phosphorescent main materials and synthesis and application methods thereof, belongs to the field of photoelectric material science and technology, and in particular relates to four spirofluorene xanthene organic phosphine oxide materials and application of the materials in the field of organic electronics such as organic electroluminescent materials, organic solar cells, organic field-effect tubes, dye laser, organic nonlinear optical materials, fluorescent probes and the like. The series of materials are obtained by introducing diphenyl phosphine oxide groups to the 2nd site, the 2nd and 7th sites, the 2nd' site and the 2nd' and 7th' sites of spirofluorene xanthene respectively. The series of compounds have good charge transfer performance, thermal stability and high triplet energy level (ET=-2.86eV), and can be used as main materials and applied in phosphorescent devices. When the series of compounds are applied in the organic electro-phosphorescent devices, the maximum external quantum efficiency is 10.78 percent and the maximum brightness is 8,582cd/m in the blue phosphorescent device; and in the green phosphorescent device, the maximum external quantum efficiency is 19.1 percent, and the maximum brightness is 16,943cd/m .

Studies of the esr spectra of semiquinone anions of xanthene dyes. variation in the linewidth of the phloxine semiquinone anion with the temperature and the viscosity in protic solvents

Abstract: The ESR linewidths of semiquinone anions of xanthene dyes in alkaline protic solvents were studied as functions of the temperature and the viscosity. It was found that the linewidths of phloxine semiquinone, the ESR spectra of which show three hyperfine lines due to two equivalent protons, decrease with a decrease in the temperature or an increase in the viscosity of the solvents, and vary unimolecularly. Such a variation can not be explained either by a usual “chemical exchange” process between different states or by intramolecular motion. We propose that the linewidths may be due to the modulation of the hyperfine coupling constants of H atoms; the modulation results from the dissociation and/or distortion of the hydrogen bonds.

Crystal structure of 9-(5-methylthiophen-2-yl)-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione, C18H18O3S

Abstract: Abstract C18H18O3S, orthorhombic, Cmc21 (no. 36), a = 14.463(3) Å, b = 9.780(5) Å, c = 10.848(4) Å, V = 1534.4(10) Å3, Z = 4, Rgt(F) = 0.0416, wRref(F2) = 0.1132, T = 293(2) K.

Catalyst‐Free Photochemical Activation of Peroxymonosulfate in Xanthene‐Rich Systems for Fenton‐Like Synergistic Decontamination: Efficacy of Proton Transfer Process

Abstract: Catalyst-free visible light assisted Fenton-like catalysis offers opportunities to achieve the sustainable water decontamination, but the synergistic decontamination mechanisms are still unclear, especially the effect of proton transfer process (PTP). The conversion of peroxymonosulfate (PMS) in photosensitive dye-enriched system was detailed. The photo-electron transfer between excited dye and PMS triggered the efficient activation of PMS and enhanced the production of reactive species. Photochemistry behavior analysis and DFT calculations revealed that PTP was the crucial factor to determine the decontamination performance, leading to the transformation of dye molecules. The excitation process inducing activation of whole system was composed of low energy excitations, and the electrons and holes were almost contributed by LUMO and HOMO. This work provided new ideas for the design of catalyst-free sustainable system for efficient decontamination.