Cybotactic behavior in the de Vries smectic-A* liquid-crystal structure formed by a silicon-containing molecule

Area of Science:

• Materials Science
• Condensed Matter Physics
• Crystallography

Background:

• The de Vries smectic-A* phase is a unique liquid-crystal phase.
• Understanding metastable states in liquid crystals is crucial for material design.
• Silicon-containing molecules offer novel properties in liquid crystal phases.

Purpose of the Study:

• To identify and characterize a metastable liquid-crystal structure in the de Vries smectic-A* phase.
• To investigate the influence of silicon groups on liquid crystal phase formation.
• To explore potential optoelectronic applications of these novel structures.

Main Methods:

• Depolarized reflection light microscopy to observe structural changes.
• Grazing incidence X-ray diffraction to analyze molecular ordering.
• Controlled cooling experiments on liquid crystal droplets and confined systems.

Main Results:

• A metastable batonnet structure was observed as an intermediate state during rapid cooling.
• This metastable state transitions to thermodynamically stable toric focal conic domains.
• Silicon groups were found to induce the formation of cybotactic structures within the de Vries phase.

Conclusions:

• The formation of a metastable de Vries Sm-A* structure is confirmed under specific boundary conditions.
• Silicon-containing molecules play a key role in inducing cybotactic clusters.
• The identified structures hold promise for future optoelectronic device development.