How do ions bind with complex ions

I understand how ligands bond to a complex metal ion. e.g $\ce{[Mn(CN)6]^3-}$ but how would 3 potassium ions $\ce{K3}$ bond with the complex ion to give $$\ce{K3[Mn(CN)6]}$$


I hope my question isn't two ambiguous. 




It is important to understand the bonding situation in complexes which can be difficult and, yes, complex. You probably should spend a fair amount of time discussing the σ and π interactions between manganese and the cyanido ligands including pointing out the high covalency of the $\ce{Mn-C}$ bonds causing a larger orbital difference and thereby a greater field split.


You may now also expect some complex interactions of the potassium cations with this complex. However, there is none. In a crystal structure, you would basically assume very footballs (the anionic complex) and much smaller golf balls (the potassium ions) that form an ionic crystal much like lithium iodide has two ions that vastly differ in size. As soon as you dissolve the solid in water, these ionic interactions break up completely to give way to dipole-ion interactions as if you had dissolved a simple ionic compound. Thus, while the solid state is adequately described as $\ce{K3[Mn(CN)6]}$, the dissolved state is better written as $\ce{3K+ + [Mn(CN)6]^3-}$.


Yes, it was indeed that simple.


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