Type of isomerism		Pair of examples
A)	Ionisation	i)	${\left[\mathrm{Pt}{\left({\mathrm{NH}}_3\right)}_3\mathrm{Cl}\right]}_2\left[{\mathrm{PtCl}}_4\right] \& \left[\mathrm{Pt}{\left({\mathrm{NH}}_3\right)}_2{\mathrm{Cll}}_2\right]$
B)	Linkage	ii)	$\left[\mathrm{Cr}{\left({\mathrm{NH}}_3\right)}_6\right]\left[\mathrm{Co}(\mathrm{CN}{)}_6\right] \& \left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_6\right]\left[\mathrm{Cr}(\mathrm{CN}{)}_6\right]$
C)	Coordination	iii)	$\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_5\left({\mathrm{NO}}_2\right)\right]{\mathrm{Cl}}_2 \& \left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_5\left(\mathrm{ONO}\right)\right]{\mathrm{Cl}}_2$
D)	Polymerisation	iv)	$\left[\mathrm{Co}\left({\mathrm{SO}}_4\right){\left({\mathrm{NH}}_3\right)}_5\right]\mathrm{Br} \& \left[\mathrm{Co}\left(\mathrm{Br}\right){\left({\mathrm{NH}}_3\right)}_5\right]{\mathrm{SO}}_4$

	A	B	C	D
1	i	ii	iii	iv
2	ii	i	iv	iii
3	iv	iii	ii	i
4	iv	ii	iii	i

two compounds having the same elemental composition but different molecular weights is called Polymerization isomerism 

Polymerization _ ${\left[\mathrm{Pt}{\left({\mathrm{NH}}_3\right)}_3\mathrm{Cl}\right]}_2\left[{\mathrm{PtCl}}_4\right] \& \left[\mathrm{Pt}{\left({\mathrm{NH}}_3\right)}_2{\mathrm{Cll}}_2\right]$

In a coordination isomer the total ratio of ligand to metal remains the same, but the ligands attached to a specific metal ion change

Coordination _ $\left[\mathrm{Cr}{\left({\mathrm{NH}}_3\right)}_6\right]\left[\mathrm{Co}(\mathrm{CN}{)}_6\right] \& \left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_6\right]\left[\mathrm{Cr}(\mathrm{CN}{)}_6\right]$

linkage isomerism or ambidentate isomerism is a form of isomerism in which certain coordination compounds have the same composition but differ in their metal atom's connectivity to a ligand

Linkage_  $\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_5\left({\mathrm{NO}}_2\right)\right]{\mathrm{Cl}}_2 \& \left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_5\left(\mathrm{ONO}\right)\right]{\mathrm{Cl}}_2$

The compound which give different ions in the solution, although they have same composition, are called ionization isomers and this property is known as ionization isomerism.

Ionization _ $\left[\mathrm{Co}\left({\mathrm{SO}}_4\right){\left({\mathrm{NH}}_3\right)}_5\right]\mathrm{Br} \& \left[\mathrm{Co}\left(\mathrm{Br}\right){\left({\mathrm{NH}}_3\right)}_5\right]{\mathrm{SO}}_4$