Question

Select the statement of Smectic liquid crystal

• A. Mobility in two directions or no rotation
• B. Three directions or no rotation
• C. Mobility in two directions or rotation in one axis
• D. Mobility in three directions or rotation in one axis

Hint:

Liquid crystals are crucial in pharmaceutical applications, especially in transdermal and controlled drug delivery systems, due to their unique alignment and mobility characteristics.

Answer 1

The Correct Option is C

Liquid crystals are a state of matter that possess properties between those of conventional liquids and solid crystals. The smectic phase is one of the most ordered liquid crystalline phases. - Smectic liquid crystals are characterized by their molecules being arranged in distinct layers. Within each layer, the molecules are free to move (flow) in two directions (within the layer), and they exhibit rotational motion around their long axis.
- This contrasts with nematic liquid crystals, where molecules are oriented in the same direction but do not form layers.
- In smectic phases, molecular mobility is restricted compared to nematic phases but still allows some fluidity. The molecular arrangement leads to anisotropic properties, which are crucial for their applications in display technologies and drug delivery systems.
Thus, smectic liquid crystals show mobility in two directions and rotation around one axis, which corresponds to option (c).