Liquid Crystals

A collection of vocabulary flashcards highlighting key terms and concepts related to Liquid Crystals from the lecture.

Liquid Crystals (LCs)

Substances that exhibit a phase of matter with properties between those of a conventional liquid and those of a solid.

Mesophase

Intermediate phases between solid and liquid found in liquid crystal materials characterized by specific molecular ordering.

Nematic Liquid Crystals

Liquid crystals with no positional order but possess orientational order.

Cholesteric Phase

A chiral nematic phase characterized by layers of molecules that form a helical structure.

Smectic Liquid Crystals

Liquid crystals that form well-defined layers that can slide over one another, exhibiting positional order.

Thermotropic Liquid Crystals

Liquid crystals that are formed by a change in temperature.

Lyotropic Liquid Crystals

Liquid crystals that consist of two or more components and exhibit liquid crystalline properties in certain concentration ranges.

Anisotropic

A property of materials that have different values of a physical property when measured along different directions.

Calamitic Liquid Crystals

Rod-shaped liquid crystals that can exhibit nematic or smectic phases.

Discotic Liquid Crystals

Disc-shaped liquid crystals that can exhibit columnar or discotic nematic phases.

Pitch

The distance over which the director of a cholesteric liquid crystal makes a complete turn.

Critical Micelle Concentration (CMC)

The concentration of surfactants above which micelles form.

Polymer Liquid Crystals (PLCs)

Materials that combine properties of polymers and liquid crystals, exhibiting similar mesophases.

Optical Switch

A device that uses light induction to trigger the opening or closing of an optical circuit.

LCD (Liquid Crystal Display)

A passive display technology that alters light traveling through it to display images.

Electro-optic effect

The change in the optical properties of a material in response to an applied electric field.

Intermolecular Attraction

The force that causes molecules to align or orient themselves with respect to each other.

Dipole Moment

A measure of the separation of positive and negative electrical charges within a molecule.

Applications of LCs

Liquid crystals are used in displays, optical devices, thermometers, battery indicators, mood rings, and various biomedical applications.