coordination number

American  

noun

Crystallography.

1. the number of anions surrounding a single cation in a stable crystal structure.

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coordination number British  

noun

1. chem the number of coordinated species surrounding the central atom in a complex or crystal

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Etymology

Origin of coordination number

First recorded in 1905–10

Example Sentences

Thus, an atom in a BCC structure has a coordination number of eight.

From Textbooks • Feb. 14, 2019

Atoms in a CCP structure have a coordination number of 12 because they contact six atoms in their layer, plus three atoms in the layer above and three atoms in the layer below.

From Textbooks • Feb. 14, 2019

In this case, the number of ligands and the coordination number are equal.

From Textbooks • Feb. 14, 2019

In this arrangement, each atom touches 12 near neighbors, and therefore has a coordination number of 12.

From Textbooks • Feb. 14, 2019

For transition metals with a coordination number of four, two different geometries are possible: tetrahedral or square planar.

From Textbooks • Feb. 14, 2019