Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Study on the Mechanism of Diarylethene Crystal Growth by In Situ Microscopy and the Crystal Growth Controlled by an Aluminum Plasmonic Chip

The microcrystalline film of an open-ring isomer (<b>1o</b>) of diarylethene <b>1</b> was prepared on an Al plasmonic chip with a grating structure. Photoisomerization from <b>1o</b> to the closed-ring isomer (<b>1c</b>) and growth of needle-shaped crystals in <b>1c</b> were observed in situ under an upright-inverted microscope. In the center part of the film, crystal growth of needle-shaped-crystal of <b>1c</b> was observed upon UV irradiation from the top side, but not upon UV irradiation from the bottom side. However, crystallization occurred at the edge of the film upon UV irradiation from the bottom side. It was suggested that crystal growth of <b>1c</b> required a high mobility of <b>1c</b> near the film surface. Furthermore, the existence of <b>1o</b> platform is also found to be required for alignment of <b>1c</b> molecules by the results under the irradiation from the bottom and top sides. With the Al plasmonic chip, the conversion rate from <b>1o</b> to <b>1c</b> was larger inside the grating by the plasmonic enhanced field. Therefore, when the attenuated UV light was irradiated to the film edge with high mobility of <b>1c</b> from the bottom side, the conversion rate was more than 60%, and the needle-shaped crystals of <b>1c</b> were observed only inside the grating area. Crystal growth was controlled by the conversion rate of <b>1c</b> promoted inside the grating. From the above, the larger conversion rate of <b>1c</b> more than 60%, a high mobility of <b>1c</b> near the film surface or edge, and the existence of the <b>1o</b> platform for alignment of <b>1c</b> molecules, are considered to be required for crystal growth in <b>1c</b>

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Efficient Surface Peeling, a Photoinduced Result of Photochromic Diarylethene Crystal by Multistep Light Irradiation

Photomechanical materials driven by an external light stimulus have become the focus of much attention. We can operate them in a noncontact way and remotely. Photoinduced bending, one of the typical photomechanical behaviors, is often observed in elongated and thinner crystals, which makes them a promising candidate for a variety of applications. However, the preparation of crystals appropriate for bending behavior is difficult because of the complexity of their molecular structures, preparation conditions, and other factors. Here, an efficient surface peeling of crystals by multistep light irradiation using diarylethene crystals is reported. Thin crystals fabricated by this approach make up less than half the thickness of the original crystals. This shows the potential for the photocontrol of various photomechanical behaviors by the same crystal depending on the irradiation conditions

Photochromism of 1,2-Bis(2-thienyl)perfluorocyclopentene Derivatives: Substituent Effect on the Reactive Carbon Atoms

In this work, we prepared a new 1,2-bis­(3-cyanothiophen-2-yl)­perfluorocyclopentene with electro-withdrawing cyano groups at both reactive carbon atoms. Furthermore, we studied the substituent effects of the reactive carbon atoms on the photochromic properties of 1,2-bis­(3-R-substituted thiophen-2-yl)­perfluorocyclopentene derivatives by comparing the absorption wavelengths and quantum yields of the derivatives having R = cyano, methyl, and methoxy groups. The absorption bands of the closed-ring isomers generated by UV irradiation shifted to longer wavelengths with an increase in the electron-donating characteristic of the substituents. The closed-ring isomer having cyano groups at both reactive carbon atoms has an absorption band at 427 nm (λ_max), whereas those of methyl and methoxy derivatives have bands at 432 and 481 nm, respectively. The derivative with cyano groups shows the largest cycloreversion quantum yield (0.45), and this yield decreased with an increase in the substituents’ donating characteristic. Theoretical calculation explains that the excited state of the closed-ring isomer with cyano groups has the highest energy, because there is no barrier to ring-opening on the excited potential surface