Simple hexagonal

Definition

Simple hexagonal refers to a type of crystal structure characterized by a hexagonal lattice system with one atom per lattice point. This structure is defined by its unique arrangement where atoms are positioned at the corners of a hexagon and one atom at the center of the hexagonal face. It plays an essential role in understanding the spatial organization and symmetry properties of various materials within solid-state physics.

5 Must Know Facts For Your Next Test

1. The simple hexagonal lattice has a two-dimensional base and extends vertically to create a three-dimensional structure, making it distinct from other crystal systems.
2. This lattice system has a coordination number of 6, meaning each atom has six nearest neighbors, which significantly impacts its physical properties.
3. Common materials that exhibit simple hexagonal structures include zinc, cadmium, and certain types of graphite.
4. The unit cell of a simple hexagonal lattice can be described by two parameters: the length of the sides of the hexagon and the height between adjacent layers.
5. The simple hexagonal structure allows for specific slip systems that influence how materials deform under stress, which is vital in material science.

Review Questions

• Compare simple hexagonal to other types of Bravais lattices in terms of symmetry and atomic arrangement.
  • Simple hexagonal differs from other Bravais lattices due to its specific atomic arrangement and symmetry properties. While cubic lattices feature more symmetry with equal distances between all neighboring atoms, simple hexagonal exhibits a unique hexagonal pattern that influences its coordination number and physical properties. This difference impacts how materials crystallize and their subsequent behaviors under various conditions.
• Discuss how the coordination number in a simple hexagonal lattice affects its physical properties compared to a face-centered cubic structure.
  • In a simple hexagonal lattice, the coordination number is 6, meaning each atom interacts closely with six neighbors, leading to specific mechanical properties such as ductility and strength. In contrast, a face-centered cubic (FCC) structure has a coordination number of 12, allowing for more robust atomic interactions. This difference results in FCC materials typically exhibiting greater malleability and toughness than those with a simple hexagonal structure.
• Evaluate the significance of simple hexagonal structures in industrial applications and material science research.
  • Simple hexagonal structures are crucial in various industrial applications due to their unique mechanical and thermal properties. Materials like zinc and magnesium, which crystallize in this form, are widely used in automotive and aerospace industries for their lightweight yet durable characteristics. Furthermore, understanding these structures aids material scientists in developing new alloys and composites tailored for specific applications by manipulating the underlying crystal geometry.

Related terms

Hexagonal close packing: A dense packing arrangement in which atoms are closely packed in a repeating hexagonal pattern, maximizing space efficiency.

Bravais lattices:

Distinct lattice types that describe the periodic arrangement of points in space, with 14 unique structures categorized into different systems, including simple hexagonal.

Coordination number: The number of nearest neighbor atoms surrounding a central atom in a crystal structure, which influences the properties and stability of materials.