Crystalline System

Question 1

Materials in which atoms are situated in a repeating or periodic array over large atomic distances

Answer 1

Crystalline Materials

Question 2

3D set of points coinciding with atom positions (or sphere centers)

Answer 2

Lattice

Question 3

Basic Structural unit or building block of the crystal structure

Answer 3

Unit Cell

Question 4

Does not have definite crystal structure like glasses

Answer 4

Amorphous material

Question 5

Different crystal structure due to prevailing temperature and pressure

Answer 5

Allotrope

Question 6

Axes and angle bet. axes?

Cubic

Answer 6

1. a = b =c
2. All angles equal to 90°

Question 7

Axes and angle bet. axes?

Tetragonal

Answer 7

1. a = b ≠ c
2. All angles equal to 90°

Question 8

Axes and angle bet. axes?

Orthorhombic

Answer 8

1. a ≠ b ≠ c
2. All angles equal to 90°

Question 9

Axes and angle bet. axes?

Rhombohedral

Answer 9

1. a = b = c
2. All angles equal but none equals 90°

Question 10

Axes and angle bet. axes?

Hexagonal

Answer 10

1. a = b ≠ c
2. Two angles equal to 90°, one equal to 120°

Question 11

Axes and angle bet. axes?

Monoclinic

Answer 11

1. a ≠ b ≠ c
2. Two angles equal to 90°