Chapter 21, Problem 21.47E

Interpretation Introduction

Interpretation:

The coordination number of the ions in the fluorite and rutile unit cells is to be determined. The reason as to why fluorite and rutile unit cells have two unequal coordination numbers, whereas cesium chloride, sodium chloride, and zincblende unit cells have only one coordination number is to be stated.

Concept introduction:

A unit cell of the crystal is the three-dimensional arrangement of the atoms present in the crystal. The unit cell is the smallest and simplest unit of the crystal which on repetition forms an entire crystal. Unit cell can be a cubic unit cell or hexagonal unit cell. The classification of a unit cell depends on the lattice site occupied by the atoms.