Trigonal columnar self-assembly of bent phasmid mesogens.

Area of Science:

• Materials Science
• Organic Chemistry
• Crystallography

Background:

• Liquid crystals are materials with properties between those of conventional liquids and solid crystals.
• Columnar liquid crystals exhibit ordered arrangements of molecules in columns, offering potential for advanced applications.
• Designing molecules with specific symmetries and self-assembly properties is crucial for controlling liquid crystal phases.

Purpose of the Study:

• To synthesize novel compounds with a bent rod-like aromatic core and alkoxy chains.
• To investigate the liquid crystalline properties and phase behavior of the synthesized compounds.
• To characterize the symmetry and structural features of the observed liquid crystal phase.

Main Methods:

• Synthesis of three target compounds utilizing click reaction chemistry.
• Characterization of the synthesized compounds using standard organic chemistry techniques.
• Polarized optical microscopy and X-ray diffraction to determine liquid crystal phase behavior and symmetry.

Main Results:

• Successful synthesis of three compounds featuring a bent aromatic core with tri-alkoxy substituents.
• Observation of a columnar liquid crystal phase in the synthesized compounds.
• Determination of non-centrosymmetric trigonal p31m symmetry for the columnar phase, with columns displaying a 3-arm star-like cross-section.

Conclusions:

• The synthesized compounds self-assemble into a unique columnar liquid crystal phase.
• The molecular architecture, featuring a bent core and alkoxy chains, dictates the formation of star-shaped columns.
• This study provides insights into the structure-property relationships for designing novel liquid crystalline materials with specific symmetries.