Papers by Author: Gang Liu

Abstract: A novel unsymmetrical photochromic diarylethene compound 1-(2-methyl-3-benzothienyl)-2-[3-methyl-2-thienyl] perfluorocyclopentene was designed and constructed successfully. Its optoelectronic properties have been discussed systematically, such as photochromic, fluorescence switch, kinetics experiments in hexane solution and PMMA. The consequences showed that this compound exhibited good reversible photochromism. The maxima absorption of compound closed-ring isomer 1c is 468nm. Upon irradiation with 297nm UV light, Its fluorescence intensity decreased along with the photochromism from open-ring isomers to closed-ring isomers upon irradiation with 297 nm UV light.

Abstract: A new unsymmetrical photochromic diarylethene 1-(2-methyl-5-phenyl-3-thiophene)-2-[2-methyl-5-phenyl-(4-vinyl)-3-thiophene] perfluorocyclopentene (1o) has been synthesized, and its photochromic reactivity, fluorescent were also investigated. The results showed this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light in solution,Diarylethene 1 changed the color from colorless to blue upon irradiation with 297 nm UV light, in which absorption maxima were observed at 596 nm in acetonitrile.

Abstract: A new symmetrical photochromic diarylethene 1,2-bis [2-methyl-5-(9,9-dihexyl-fluorene)-3-thienyl] perfluorocyclopentene (1o) has been synthesized, and its optoelectronic properties, such as photochromism and the fluorescence spectra of diarylethene 1o in acetonitrile solution was investigated. The maxima absorption of compound closed-ring isomer 1c is 619 nm. The open-ring isomer of the diarylethene 1o exhibited fluorescence at 390 nm. Its fluorescence intensity decreased along with the photochromism from open-ring isomers to closed-ring isomers upon irradiation with 297 nm UV light,The results showed that this compound exhibited reversible photochromism and fluorescent switching in solution after irradiation with UV light and visible light.

Abstract: A novel photochromic diarylethene bearing a pyrimidine moiety, 1-(2,4-dimethoxyl-5-pyrimidinyl)-2-[2-methyl-5-(3-cyano)-3-thieny-l] perfluorocyclopentene has been synthesized. Its properties, including photochromic behavior and fluorescent properties, have been investigated. The compound exhibited remarkable photochromism, changing from colorless to blue after irradiation with UV light. The results indicated that the pyrimidine moiety played a very important role during the process of photoisomerization reactions.

Abstract: A new asymmetrical photochromic diarylethene 1-(2-cyano-1,5-dimethyl-4-pyrryl)-2-{2-methyl-[5-(4-methylene-hydroxyl) phenyl]-3-thienyl} perflu-orocyclopentene (1o) was synthesized and its photochromic properties were investigated systematically. Upon irradiation with 297 nm UV light, 1o exhibited photochromism in acetonitrile solution and in a PMMA amorphous film. The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively. In addition, diarylethene 1o also exhibited obvious fluorescence switches along with the photochromism.

Abstract: A new symmetrical photochromic diarylethene, 1,2-bis-[2-methyl-5-(9,9-dibutyl-9H-fluorene) -3-thienyl] perfluorocyclopentene (1a), was synthesized and its optoelectronic properties, such as photochromism in solution and fluorescence were investigated. The photochromic reaction kinetics indicated that the cyclization processes of 1a belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction. The new diarylethene also exhibited relatively strong fluorescence by photoirradiation in solution and the fluorescence intensity decreased along with the photochromism upon irradiation 297 nm light and its closed-ring isomer showed almost no fluorescence.

Abstract: A novel isomeric photochromic diarylethene, 1-(2-methyl-5-phenyl-3-thienyl)-2-[2-methyl-5-(4-pentylphenyl)-3-thienyl] perfluorocyclopentene, was designed and synthesized. Its fluorescent and photochromic properties were also studied in detail. The compound exhibited excellent photochromism, changing from colorless to bule after irradiation with UV light both in solution and in PMMA film. In addition, the fluorescence intensity of the photochromic diarylethene 1a declined remarkably, when irradiation with UV light.

Abstract: A new unsymmetrical photochromic diarylethene compound, 1-(2-methyl-3-benzothienyl)-2-(2-methyl-(5-ethynyl) trimethylsilane-3-thienyl) perfluorocyclopentene (1o) has been synthesized, and its optoelectronic properties, such as photochromism and the fluorescence spectra of diarylethene 1o in hexane solution was investigated. The results showed that this compound exhibited reversible photochromism in solution. The maxima absorption of compound closed-ring isomer 1c are 538 nm. Its fluorescence intensity decreased along with the photochromism from open-ring isomers to closed-ring isomers upon irradiation with 297 nm UV light.

Abstract: A new photochromic diarylethene having a pyrrole unit, which is named 1-(2-cyano-1,5-dimethyl-4-pyrryl)-2-{2-methyl-[5-(4-methylene-bromine) phenyl]-3-thienyl} perfluorocyclopentene, was designed and constructed successfully. And its properties have been discussed systematically, including photochromic, fluorescence switch and kinetics experiments in acetonitrile solution. The results showed that its photochromic behaviors could be modulated by UV/Vis light, changing from colorless to blue in acetonitrile solution. What is more, the kinetic experiments illustrated that the cyclization/cycloreversion process of this compound was determined to be the zeroth/first reaction.

Abstract: A new class of unsymmetrical photochromic diarylethene bearing an isoxazole moiety was synthesized. Its photochemical properties, including photochromic behavior and kinetics, have been investigated systematically. The result indicated that the Diarylethene 1a changed the color from colorless to pink irradiation with 297 nm UV light, in which absorption maxima were observed at 522 nm in hexane. The photochromic reaction kinetics indicated that the cyclization processes of 1a belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction.