Thermotropic properties and molecular packing of discotic tristriazolotriazines with rigid substituents.
Tristriazolotriazines with a threefold dialkoxyaryl substitution have been prepared by Huisgen reaction of cyanuric chloride and the corresponding tetrazoles. Although these dyes show a negative or inverted solvatochromism of the UV/Vis absorption, their fluorescence is strongly positive solvatochromic. These discotic fluorophores are also emissive in their solid state and in their broad liquid-crystalline mesophase. The structural study indicates that the thermotropic properties and organization of these systems can be well tuned by the steric demand of the aryl groups. Depending on the substituents, the compounds showed either a pure crystalline phase or a highly complex helical superstru…
Tetrakis(oxadiazolylphenyl)pyrazines: New St. Andrew's Cross-Shaped Liquid Crystals.
π-Conjugated molecules with the shape of St. Andrew's cross have been synthesized via fourfold Huisgen reaction. Four 2,5-diaryl-1,3,4-oxadiazol arms are attached to a central pyrazine nucleus. These fluorescent stars, when decorated with a rim of eight alkoxy side chains are discotic liquid crystals. Depending on the substitution pattern, the width of the liquid phase varies within a broad range of 25 °C to 250 °C. In their liquid crystalline phase, the molecules assemble in a typical hexagonal columnar supramolecular arrangement.
Dicyanobenzothiadiazole Derivatives Possessing Switchable Dielectric Permittivities
Benzothiadiazoles are important electron acceptors and are frequently employed as electron-deficient components of donor-acceptor polymers. We report the effect of nitrile functionalities on the reactivity, steric hindrance, optoelectronic properties, and dielectric permittivity in dicyanobenzothioadiazole (DCNBT). Dielectric spectroscopy in the bulk and in solution assisted by DFT-calculations revealed that these molecules can be engineered to engender maximum values of the dipole moment and of dielectric permittivity due to the strong electron-withdrawing effect of the nitrile groups. The self-assembly in the bulk was investigated by X-ray scattering performed on single crystals, fibers (…
CCDC 1533973: Experimental Crystal Structure Determination
Related Article: Jakob Wudarczyk, George Papamokos, Tomasz Marszalek, Thomas Nevolianis, Dieter Schollmeyer, Wojciech Pisula, George Floudas, Martin Baumgarten, and Klaus Müllen|2017|ACS Applied Materials and Interfaces|9|20527|doi:10.1021/acsami.7b03060
CCDC 1826069: Experimental Crystal Structure Determination
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CCDC 1533972: Experimental Crystal Structure Determination
Related Article: Jakob Wudarczyk, George Papamokos, Tomasz Marszalek, Thomas Nevolianis, Dieter Schollmeyer, Wojciech Pisula, George Floudas, Martin Baumgarten, and Klaus Müllen|2017|ACS Applied Materials and Interfaces|9|20527|doi:10.1021/acsami.7b03060
CCDC 1533971: Experimental Crystal Structure Determination
Related Article: Jakob Wudarczyk, George Papamokos, Tomasz Marszalek, Thomas Nevolianis, Dieter Schollmeyer, Wojciech Pisula, George Floudas, Martin Baumgarten, and Klaus Müllen|2017|ACS Applied Materials and Interfaces|9|20527|doi:10.1021/acsami.7b03060
CCDC 1533733: Experimental Crystal Structure Determination
Related Article: Jakob Wudarczyk, George Papamokos, Tomasz Marszalek, Thomas Nevolianis, Dieter Schollmeyer, Wojciech Pisula, George Floudas, Martin Baumgarten, and Klaus Müllen|2017|ACS Applied Materials and Interfaces|9|20527|doi:10.1021/acsami.7b03060
CCDC 1533970: Experimental Crystal Structure Determination
Related Article: Jakob Wudarczyk, George Papamokos, Tomasz Marszalek, Thomas Nevolianis, Dieter Schollmeyer, Wojciech Pisula, George Floudas, Martin Baumgarten, and Klaus Müllen|2017|ACS Applied Materials and Interfaces|9|20527|doi:10.1021/acsami.7b03060
CCDC 1533734: Experimental Crystal Structure Determination
Related Article: Jakob Wudarczyk, George Papamokos, Tomasz Marszalek, Thomas Nevolianis, Dieter Schollmeyer, Wojciech Pisula, George Floudas, Martin Baumgarten, and Klaus Müllen|2017|ACS Applied Materials and Interfaces|9|20527|doi:10.1021/acsami.7b03060