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Which geometries can occur in coordination compounds with five ligands?

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Structural diagram of the vitamin B12 coenzyme molecule, highlighting its organometallic core with five nitrogen-cobalt bonds and one cobalt-carbon bond at the center, surrounded by complex organic groups. — coordination compound Coordination compounds contain a central metal atom surrounded by nonmetal atoms or groups of atoms, called ligands. For example, vitamin B₁₂ is made up of a central metallic cobalt ion bound to multiple nitrogen-containing ligands.

In coordination chemistry, coordination compounds with a coordination number of five can exhibit two primary geometries:

Trigonal bipyramid: An arrangement where the ligands are positioned at the vertices of two triangular pyramids joined at their bases.1
Square pyramid: An arrangement where four ligands form a square base with the fifth ligand positioned above the center of that base.1

These structures are determined by factors such as the relative sizes of the metal atom and ligands, steric constraints of polydentate ligands, and the electronic configuration of the metal ion.1