📂Physics

Crystal Structure

Definition

An arrangement of atoms, molecules, ions, etc., that periodically repeats in a three-dimensional space is called a crystal.

Description¹

A crystal structure refers to the basic structural unit of solid materials, where atoms or molecules are arranged in a regular pattern. This structure greatly influences the physical and chemical properties of the material. For instance, in the illustration below, on the left, carbon atoms $\ce{C}$ are repeated in a hexagonal planar structure, representing the crystal structure of graphite. On the right, although carbon atoms $\ce{C}$ are likewise repeated, they are arranged in a three-dimensional configuration characteristic of diamond’s crystal structure. Despite carbon atoms being regularly arranged in both cases, the structure results in graphite being soft and electrically conductive, whereas diamond is hard and an insulator.