What is coordination number?

Coordination number is the number of atoms, ions, or molecules surrounding a central atom in a complex or a crystal. It is an important concept in chemistry and crystallography that helps determine the structure and stability of a compound.

In coordination complexes, the coordination number indicates the number of ligands attached to the central metal ion. The most common coordination numbers are 2, 4, and 6, although other coordination numbers are also possible depending on the size and charge of the central metal ion.

In crystals, the coordination number refers to the number of nearest neighbors surrounding a particular atom in the crystal lattice. The coordination number can vary depending on the crystal structure and the type of packing arrangement of atoms or ions in the crystal lattice.

Overall, coordination number provides important information about the bonding and geometry of a molecule or crystal, and it can help predict the physical and chemical properties of a compound.