Question

explain the different types of crystal system with their parameters and examples. (please don't spam)​

Answer 1

Crystal System Example

Cubic a = b = c; α = β = γ = 90° Pyrite

Tetragonal a = b ≠ c; α = β = γ = 90° Wulfenite

Orthorhombic a ≠ b ≠ c; α = β = γ = 90° Aragonite

Monoclinic a ≠ b ≠ c; α ≠ 90° = β = γ Azurite

Answer 2

The different types of crystal system  are cubic, tetragonal, hexagonal, monoclinic, triclinic, orthorhombic, and rhombohedral.

• Depending upon the shapes, crystals are categorized into broad classification. A crystal is characterized by the number of its faces, which intersect or bisect with each other at certain angles.
• These angles are distinct for different substances. The crystal systems are divided into seven types.
• A crystal can depict the length of its edge with the help of letters a, b and c.
• While the angles at which the faces of the crystals bisects can be depicted with the help of Greek letters α, β, γ
• All the seven types of crystal systems have differences in terms of the number of edges and on each face, the length of the edges are equal. The angles formed between the faces are same.
• Seven crystal systems along with their examples are as follow:
• Cubic:

         $\alpha$ = $\beta$ =  $\gamma$ = 90°; a =b = c. Example pyrite.  

• Tetragonal:

          $\alpha$ = $\beta$ = $\gamma$ = 90°; a = b ≠c. Example Wulfenite.

•  Orthorhombic:

          $\alpha$ = $\beta$ = $\gamma$ = 90°; a ≠b ≠c. Example Aragonite.

• Triclinic:  

          $\alpha$ ≠ $\beta$ ≠ $\gamma$ ≠ 90°; a ≠ b ≠c. Example Microcline.

• Rhombohedral:

          $\alpha$ = $\beta$ = $\gamma$ ≠ 90°; a = b = c. Example Calcite.

• Hexagonal:

          $\alpha$ = $\beta$ = 90°; $\gamma$ = 120°; a = b ≠ c. Example Beryl.

• Monoclinic

          $\alpha$ ≠ 90° = $\beta$ = $\gamma$; a ≠ b ≠ c. Example Azurite.

Hence, Cubic, tetragonal, hexagonal, monoclinic, triclinic, orthorhombic, and rhombohedral are seven types of crystal systems.