In octahedral holes (voids):

Options

A. A simple triangular void surrounded by four spheres
B. A bi-triangular void surrounded by four spheres
C. A bi-triangular void surrounded by six spheres
D. A bi-triangular void surrounded by eight spheres

Answer

To solve the question regarding octahedral holes (voids), we can follow these steps:

### Step 1: Understand the Structure of Octahedral Voids
Octahedral voids are formed in a crystal lattice where atoms are arranged in a specific geometric configuration. In a typical face-centered cubic (FCC) lattice, octahedral voids are located at the center of the cube and at the edges.

### Step 2: Visualize the Arrangement
In an FCC lattice, consider the arrangement of atoms:
- Atoms are located at each corner of the cube and at the center of each face.
- The octahedral void is created by the arrangement of these atoms.

### Step 3: Identify the Surrounding Atoms
In the case of octahedral voids:
- There are 6 atoms surrounding the void.
- These atoms are positioned at the vertices of an octahedron.

### Step 4: Analyze the Options
Given the options, we need to identify which one correctly describes the octahedral void:
- The correct description will mention that the void is surrounded by 6 spheres (atoms).

### Step 5: Select the Correct Option
Based on the analysis, the correct option is:
**C: A bi-triangular void surrounded by six spheres.**

### Final Answer
The correct option regarding octahedral holes is **C**.

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