Question

BaTiO3 has perovskite structure with Ba2+ ions at the corners, O2– ions at the center of each face and Ti4+ ions at the center of a cubic unit cell. What is the number of Ti4+ ions nearest to Ba2+ ion?

Answer 1

There is one Ti4+ ion nearest to Ba2+ ion

Explanation:

The structure of Barium Titanate is a perovskite structure or a cubic lattice.

Ba2+ ions are at the corners of unit cell.

The unit cell has 8 face centre positions, each contributing 1/8 to the unit cell.

There is  8/8 = 1 Ba2+ ion per unit cell.

Oxide ions at the face centers: There are six face center positions each contributing 1/2 to the unit cell.

There are  6/2 = 3 oxide ion per unit cell.

Titanium ions are at the body center.

There is one body center position contributing one to the unit cell.

There is one Ti4+ ion per unit cell.

Therefore the molecular formula of barium titanate is BaTiO3.