The basic structural unit or building block of the crystal structure and defines the crystal structure by virtue of its geometry and the atom positions within

Cube edge length a or x and the atomic radius R in FCC is related by

In order to compute the number of atoms per unit cell for the HCP crystal structure we will use

The sum of the sphere volumes of all atoms within a unit cell (assuming the atomic hard-sphere model) divided by the unit cell volume

When metals and nonmetals have more than one crystal structure

Allotropy is

There are nine different possible combinations of which represents a distinct crystal system.

Crystallography

Defined as a line directed between two points, or a vector

Defined as the number of atoms per unit length whose centers lie on the direction vector for a specific crystallographic direction

Taken as the number of atoms per unit area that are centered on a particular crystallographic plane

The result when the periodic and repeated arrangement of atoms is perfect or extends throughout the entirety of the specimen without interruption

Spheres representing nearest-neighbor atoms touch one another.

Means a three-dimensional array of points coinciding with atom positions

Long-range atomic order is absent

Long-range order exists

Grain boundary is a

The number of switches (transistors) that can fit on a single computer chip has doubled

Which of the given cubic structure has the highest packing factor

Coordination number ofis the characteristic of