Two novel diarylethene derivatives bearing a rhodamine unit have been successfully synthesized. Their unique multi-addressable switching characteristics as induced by chemical and optical dual inputs stimulation were observed using UV and FL measurements. The two diarylethenes showed excellent photochormism with alternating UV/vis light irradiation. Addition of trifluoroacetic acid (TFA) protonated the diarylethenes, which resulted in good photochromism and notable fluorescence change via the FRET mechanism. Subsequent addition of triethanolamine base would neutralize and return both their protonated open-ring and closed-ring isomers to their original forms. It was found that the diarylethene bearing a rhodamine unit linked by a benzhydrazide bridge group was more sensitive, efficient and reacted faster to protonation by TFA when compared to the benzamide bridged derivative. Furthermore, the benzhydrazide bridged diarylethene derivative was found to be selective towards Cr(III), Al(III), or Ca(II) with significant color and fluorescence changes.

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A new fluorescent probe 1O was synthesized through linking diarylethene and Quinoxaline-2-hydraqzide group, probe 1O showed a selective "off-on" fluorescent response toward Mg 2+ . In the presence of Mg 2+ , the probe 1O displayed a distinct change of fluorescence color, from dark to green, the fluorescence intensity increased 6.8-fold, and meanwhile, emission peak has a significant blue shift, which was shifted from 524 nm to 518 nm. Then, on account of the fluorescence properties of compound 1O, we designed a logic gate. On top of that, probe 1O also can be successfully used to monitor Mg 2+ of the actual water samples.

An unsymmetrical diarylethene derivative 1-(2,5-dimethyl-3-thienyl)-2-[2-methyl-5-(4-hydroxylphenyl)-3-thienyl]hexafluorocyclopentene (1a) was synthesized. At the same time, 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 547 nm in hexane and at 554 nm in PMMA amorphous film, respectively, upon irradiation with 297 nm UV light. The fluorescence intensity of diarylethene decreased dramatically along with the photochromism from open-ring isomer to closed-ring isomer upon irradiation with 297 nm UV light in hexane. In hexane the open-ring isomer of the diarylethene 1 exhibited relatively fluorescence at 507 nm when excited at 375 nm. This new photochromic compound also exhibited remarkable optical storage character.