Question

Diamond exhibits which type of structures:

• A. Hexagonal and orthorhombic
• B. Orthorhombic and tetragonal
• C. Trigonal and monoclinic
• D. Cubic and hexagonal

Hint:

Remember the common crystal structures of key materials. Carbon is a great example with multiple important allotropes: diamond (cubic), graphite (hexagonal), and Lonsdaleite (hexagonal diamond). Knowing these helps in quickly identifying correct options.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
This question asks about the possible crystal structures of diamond. Diamond is an allotrope of carbon. We need to identify the known crystallographic forms of diamond.
Step 2: Detailed Explanation:
The most common and stable form of diamond has a crystal structure known as the diamond cubic lattice. This structure belongs to the cubic crystal system. It can be thought of as two interpenetrating face-centered cubic (FCC) lattices.
There is another, less common, allotrope of carbon called Lonsdaleite, which is also known as hexagonal diamond. As its name suggests, Lonsdaleite has a hexagonal crystal structure. It is found in nature in some meteorites and can be synthesized in the lab.
Therefore, diamond and its related structures can exist in both cubic and hexagonal forms.
Step 3: Final Answer:
Diamond exhibits both cubic and hexagonal structures.