Papers by Author: Wei Jun Liu

Abstract: A new unsymmetrical photochromic diarylethene 1-(2-methyl-benzofuran-3-yl)-2-(2-n-butyl-5-(1,3-dithiolane)-thiophene-3-yl) perfluoroncyclopentene (1o), was synthesized and its optoelectronic properties, such as photochromism in solution as well as in poly-methylmethacrylate (PMMA) amorphous films, and the fluorescence spectra of diarylethene 1a was investigated. Using diarylethene 1c/PMMA film as recording medium and a linearly polarized 633 nm laser diode for recording and readout, polarization multiplexed image recording can be carried out in this film, which illustrated that the diarylethene can be potentially used as holographic optical recording medium.

Abstract: A novel photochromic diarylethene，1-(3,5-dimethyl-4-isoxazolyl)-2-[2-methyl-5-(10-phenanthrenyl)-3-thienyl]Perfluorocyclopentene was synthesized and its photochromic and fluorescent properties were also investigated. The compound exhibited remarkable photochromism, changing from colorless to pink after irradiation with UV light both in solution and in PMMA film. The fluorescence intensity declined remarkably，when irradiation with UV light. Using this diarylethene 1 as optical storage was performed successfully.

Abstract: A novel photochromic diarylethene based on isoxazole moiety was synthesized and its photochromic and fluorescent properties were also investigated. The compound exhibited remarkable photochromism, changing from colorless to purple after irradiation with UV light both in solution and in PMMA film. In hexane solution and in PMMA film, the open-ring isomer of the diarylethene 1 exhibited relatively remarkable fluorescence. The results indicated that the isoxazole moiety played a very important role during the process of photochromic reaction for the diarylethene derivative. Using this dithienylethene 1c as optical storage was performed successfully.

Abstract: An unsymmetrical diarylethene derivative was synthesized, and its photochromic properties and fluorescence switch were investigated in detail. The results showed that this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in PMMA film, and its absorption maxima were observed at 548 nm in hexane and at 558 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light. The PMMA film of the diarylethene 1a exhibited relatively strong fluorescence at 413 nm when excited at 311 nm. The fluorscence intensity is highest at the concentration of 1.0×10^-4 mol/L when excited at 311 nm.

Abstract: A new purple photochromic diarylethene compound, [1- (2-ethyl-3-benzothienyl)-2-(1,3,5-trimethyl-4-pyrazolyl)]perfluoroclopentene (1a), was synthesized and its photochemical properties were investigated in detail. The results demonstrated that the compound has good photochromism in PMMA amorphous film and fluorescence switching properties.

Abstract: A novel unsymmetrical photochromic diarylethene compound bearing dithiol-pentane unit, 1-[2-methyl-5-(1,3-dithiol-pentane)-3-thienyl]-2-[2-methyl-3-benzofuran-yl]perfluoroyclopentene(1a) has been synthesized, and its photochromic, fluorescence and optical recording strorage properties were investigated. The compound exhibited remarkable photochromism and clear fluorescent switches both in solution and in PMMA film. Using diarylethene 1b/PMMA film as recording medium and a linearly polarized 650 nm laser diode for recording and readout, polarization multiplexed image recording can be carried out in this film. The results demonstrated that the diarylethene can be potentially used as polarization multiplexing holographic recording medium.

Abstract: A novel unsymmetrical diarylethene derivative 1-[2-methyl-5-(3-trifluoromethylphenyl)-3-thienyl]-2-[2-methyl-5-(4-methoxyphenyl)-3-thienyl]hexafluorocyclopentene (1a) was designed and successfully synthesized. The properties of the compound, including photochromic and electrochemical properties of the diarylethene were also investigated systematically. The results showed that this compound exhibited reversible photochromism, reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in PMMA film, and its absorption maxima were observed at 606 nm in methanol and at 613 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light. Besides, the electrochemcial switching property can be potential use for electrochemistry data storage.

Abstract: A new photochromic diarylethene bearing an isoxazole unit has been synthesized, namely {1-(3,5-dimethyl-4-isoxazolyl), 2-[2-methyl-5-(3-methoxyphenyl)-3-thienyl]}perfluorocyclopentene. Its properties, including photochromic reactivity both in solution and in PMMA film, photoconversion ratio at photostationary state, fluorescence and optical recording property were investigated. It underwent reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in hexane and in PMMA. The isomeric compound also functioned as a fluorescence switch by photoirradiation. Using this dithienylethene as optical storage was performed successfully.

Abstract: A novel unsymmetrical diarylethene derivative 1-[2-methyl-5-(3-trifluoromethylphenyl)-3-thienyl]-2-[2-methyl-5-(4-hydroxylphenyl)-3-thienyl]hexafluorocyclopentene (1a) was successfully synthesized. The properties of the compound, including photochromic and fluorescence properties of the diarylethene were also investigated systematically. The results showed that this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in PMMA film, and its absorption maxima were observed at 593 nm in methanol and at 598 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light. In methanol solution, the open-ring isomer of the diarylethene 1 exhibited relatively fluorescence at 569 nm when excited at 360 nm.

Abstract: A new photochromic diarylethene compound [1-(2-methyl-1-naphthyl), 2-(2-methyl-5-(4-dioxolanephenyl)-3-thienyl)]perfluorocyclopentene 1o was synthesized and its photochromic properties, fluorescence switch and kinetic properties were investigated in detail. Upon irradiated UV light it changes from colorless to red both in solution and in PMMA amorphous film. In addition, the kinetic experiment indicated that the cyclization/cycloreversion process belong to zeroth and first order reactions, respectively. Finally, the fluorescence spectrum of diarylethene 1o was decreased remarkable along with the cyclization reactions.