Session: Undergraduate Research Posters: Organic Chemistry:

Donor acceptor columnar liquid crystal DACLC is an interesting class of materials composed of two charge-complementary aromatic compounds that spontaneously assemble into alternating DADA columnar structures. We have previously shown that the effect of cooling rate and the direction of cooling of melted DACLCs allows for effective control over the form and alignment of these structures. This controlled assembly and the resulting optoelectronic properties make DACLC materials of interest for use in organic semiconductors, cryptography, LC displays, and data storage.
To date, the DACLC materials studied for alignment have all consisted of symmetric (C₂ or C₃ molecular components. However, the presence of an asymmetric molecular dipole may further expand control over the assembly of these materials. Exposure to an external magnetic field would then potentially orient molecular dipoles with respect to the field, orthogonal to the columnar assembly. This behavior would enable control over the orientation of these structures in three-dimensional space.
The synthesis and characterization of asymmetric aromatic components for use in these new DACLC systems is described here. This includes synthetic pathways for the development of two such asymmetrically substituted triphenylene compounds which display strong molecular dipoles. The self-assembly of these compounds and the subsequent behavior of the resulting DACLC materials will also be discussed.

Joseph Reczek

Denison University

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