Why Does NH3 Form Complex Ions with Transition Elements?

[richi]

Can anybody please tell me why NH3 readily forms complex ions with transitional elements but NH4+ doesn't?

 

[chemisttree]

Complexes of this type are generally between electron donors (ligands) and electron acceptors (empty d shell orbitals in transition metals).

 

[richi]

this is what I think ; NH3 has 2 unpaired electrons and they can bond with the d orbitals of tranisitional metals. However, NH4+ doesn't have an unpaired electron and can only substitute its H.

Am I on the right track?

 

[chemisttree]

Sounds like it...