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How are the six ligands arranged in an octahedral coordination complex?

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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 an octahedral coordination complex, the six ligands are arranged such that four are positioned in a single plane, with one ligand located above that plane and one below it.1

From the perspective of valence bond theory, this geometry is associated with $d^{2} s p^{3}$ or $s p^{3} d^{2}$ hybridization of the central metal ion's orbitals, which dictates the spatial orientation of the bonds. This arrangement is a common structural form for complexes with a coordination number of six.21