Coordination compounds exhibit stereo isomerism and structural isomerism.
Two types of stereoisomerism and their examples are as follows.
(i) Geometrical isomerism


(ii) Optical isomerism.

Four types of structural isomerism are as follows:
(i) Linkage isomerism \(\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{NO}_2\right] \mathrm{Cl}_2\) and \(\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{ONO}\right] \mathrm{Cl}_2\)
(ii) Coordination isomerism \(\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]\left[\mathrm{Cr}(\mathrm{CN})_6\right]\) and \(\left[\mathrm{Cr}\left(\mathrm{NH}_3\right)_6\right]\left[\mathrm{Co}(\mathrm{CN})_6\right]\)
(iii) Ionisation isomerism \(\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{SO}_4\right] \mathrm{Br}\) and \(\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{Br}^2 \mathrm{SO}_4\right.\)
(iv) Solvate or hydrate isomerism \(\left[\mathrm{Cr}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right] \mathrm{Cl}_2\) and \(\left[\mathrm{Cr}\left(\mathrm{H}_2 \mathrm{O}\right)_5 \mathrm{Cl}\right] \mathrm{Cl}^2 \mathrm{H}_2 \mathrm{O}\)