Crystal system

Crystal Systems

• The diamond crystal structure belongs to the face-centered cubic lattice.
• Crystal systems are sets of point groups and lattice systems.
• Crystal systems are classified into seven categories: triclinic, monoclinic, orthorhombic, tetragonal, trigonal, hexagonal, and cubic.
• Crystals in the same crystal system have similar symmetries.
• Crystal systems with space groups assigned to a common lattice system are combined into a crystal family.

Classification of Crystals

• Crystals can be classified based on lattice systems, crystal systems, and crystal families.
• Trigonal crystal system is often confused with the rhombohedral lattice system.
• The term crystal system is sometimes used interchangeably with lattice system or crystal family.

Lattice System

• A lattice system is a group of lattices with the same set of lattice point groups.
• There are seven lattice systems: triclinic, monoclinic, orthorhombic, tetragonal, rhombohedral, hexagonal, and cubic.

Crystal Family

• A crystal family is formed by combining crystal systems with space groups assigned to a common lattice system.
• Hexagonal and trigonal crystal systems are combined into the hexagonal crystal family.

Crystallographers

• J. D. Bernal
• Herman Francis Mark
• Ralph Wyckoff
• Martin Buerger
• Johannes M. Bijvoet
• Fritz Laves
• Linus Pauling
• Aaron Klug
• Dorothy Hodgkin
• Kathleen Lonsdale
• Rosalind Franklin
• Jack D. Dunitz
• Alexander F. Wells
• Crystallography Pioneers:
• Linus Pauling
• Dorothy Hodgkin
• Aaron Klug
• Kathleen Lonsdale
• Rosalind Franklin

Crystal system Data Sources