No abstract

We demonstrate an innovative technique to achieve organic 2D and 3D waveguides with peculiar shapes from an acicular, stimuli‐responsive molecular crystal, (2Z,2′Z)‐3,3′‐(anthracene‐9,10‐diyl)bis(2‐(3,5‐bis(trifluoromethyl)phenylacrylonitrile), Ant‐CF3. The greenish‐yellow fluorescent (FL) Ant‐CF3 molecular crystals exhibit laser power‐dependent permanent mechanical bending in 2D and 3D. Investigation of a single‐crystal using spatially‐resolved Raman/FL/electron microscopy, and theoretical calculations revealed photothermal (Z,E)/(E,E) isomerization‐assisted transition from crystalline to amorphous phase at the laser‐exposed regions. This phenomenon facilitates the dimension engineering of a 1D crystal waveguide into 2D waveguide on a substrate or a 3D waveguide in free space. The bends can be used as interconnection points to couple different optical elements. The presented technique has broader implications in organic photonics and other crystal‐related photonic technologies.

The first direct fabrication of A2B- and A3-type B­(III)­subchlorins from meso-ethoxycarbonyl-substituted tripyrrane has been realized by condensation with appropriate acid chlorides (benzoyl chloride, butyryl chloride, and ethyl chlorooxoacetate). The aliphatic acid chloride-based annulation reaction is new to subporphyrinoid chemistry. The phenyl (6a)- or n-propyl (6b)-substituted derivatives could be oxidized to the corresponding B­(III)­subporphyrins upon refluxing with DDQ, whereas the triethoxycarbonyl moiety (6c) was found to be resistant to oxidation and exhibits the most red-shifted absorption (587 nm) and emission (604 nm). The study indicates that absorption and emission behaviors of the B­(III)­subchlorin can be tuned by the introduction of electron-rich or electron-deficient substituents at the meso-position. B­(III)­subchlorins 6a and 6c generate singlet oxygen efficiently (44 and 40%, respectively) and, thus, may find application as potential photosensitizers in photodynamic therapy (PDT).

We demonstrate an innovative technique to achieve organic 2D and 3D waveguides with peculiar shapes from an acicular, stimuli-responsive molecular crystal, (2Z,2'Z)-3,3'-(anthracene-9,10-diyl)bis(2-(3,5bis(trifluoromethyl)phenylacrylonitrile), Ant-CF 3 . The greenish-yellow fluorescent (FL) Ant-CF 3 molecular crystals exhibit laser power-dependent permanent mechanical bending in 2D and 3D. Investigation of a single-crystal using spatially-resolved Raman/FL/electron microscopy, and theoretical calculations revealed photothermal (Z,E)/(E,E) isomerization-assisted transition from crystalline to amorphous phase at the laserexposed regions. This phenomenon facilitates the dimension engineering of a 1D crystal waveguide into 2D waveguide on a substrate or a 3D waveguide in free space. The bends can be used as interconnection points to couple different optical elements. The presented technique has broader implications in organic photonics and other crystal-related photonic technologies.