Werner formuled the complexes as [Co(NH3)6]Cl3 , [Co(NH3)5Cl]Cl2 and [Co(NH3)4Cl2]Cl where the complex
cations, (represented by the species inside the square brackets)
are discrete entities
in solution, each having
its own unique
properties.
Each Co centre
has six groups
strongly bound to it
called ligands
(Latin
"ligare", to bind)
These transition
metal complexes are
commonly called coordination
compounds.