Hybrid Molecular Orientation of Sandwich-Type Structure Discogen Hexaalkoxydibenzo[a,c]phenazine on the Surfaces Modified Using Silane Self-Assembly Monolayers

Abstract

Substrates were processed using hydrogen peroxide and coated with silane self-assembly monolayers to obtain different surface free energies. The face-on anchoring and edge-on anchoring of discogen 11,12-bisdodecyloxy-2,3,6,7-tetrakisoctyloxydibenzo[a,c]phenazine molecules were obtained on the peroxidized ITO surface and the surface covered by octadecyltrichlorosilane, respectively. It is demonstrated that substrates with patterned surface free energy template can be produced by stamp printing the silane onto and followed by a silanization process in situ on the substrates. Discogen domains with different types of columnar orientation are formed in a cell constructed using the substrates with patterned energetic template.

Keywords:

• Columnar phase
• columnar phase alignment
• discotic liquid crystal
• silane self-assembly monolayer

Acknowledgment

The authors acknowledge Prof Ong for kindly providing the discogen compound. The financial support from NEC of Taiwan through “Aim for Top Universities” scheme is also gratefully acknowledged. This study is funded by National Science Council of Taiwan (NSC982221E110008).