By far, the most common coordination numbers for coordination compounds are 2, 4 and 6. Shown below are several coordination compounds which have coordination numbers of 3, 5 and 7.
 = Hg
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| [HgCl3]- In this complex ion, the coordination number of 3 results in a trigonal planar structure. Note that the chloride ligands are bonded to the Hg atom at the corners of an equilateral triangle. |
 = Fe
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| Fe(CO)5 In this compound, the coordination number of 5 results in a trigonal bipyramidal structure. Note that three CO molecules are bonded to the Fe atom at the corners of an equilateral triangle while the other two CO molecules are bonded to the metal above and below the plane of the triangle. |
[VOCl4]2- In this compound, the coordination number of 5 results in a square pyramidal structure. Note that the four Cl ligands are bonded to the V atom at the corners of a square while the O ligand is bonded to the metal above the plane of the square. |
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= I or Nb
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| IF7 This compound is an example of a compound containing only main-group elements. The coordination number of 7 results in a pentagonal bipyramidal structure. Note that five F ions are bonded to the I atom at the corners of an pentagon while the other two F ions are bonded to the I atom above and below the plane of the pentagon. |
[NbOF6]3- In this compound, the coordination number of 7 results in a capped octahedron - triangular face structure. Note that the six F ions are bonded to the Nb atom in an octahedral arrangement. The O atom is bonded to the Nb atom at one of the triangular faces of the octahedron. |
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= Nb
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| [NbF7]2- In this compound, the coordination number of 7 results in a capped trigonal prism structure. |
= Cl
= C
= O