Thermal dissociation of solid complexes

Thermal dissociation amounts to a substitution reaction in the solid state. At some elevated temperature, volatile coordinated ligands are lost and their place in the coordination sphere is taken by the anions of the complex. A familiar example, but one that is seldom considered in this way, is the loss of water by CUSO4 5H2O when it is heated. The blue hydrate yields the almost white 

At elevated temperatures, coordinated water can often be liberated fi om solid aquoamminemetal complexes. It is sometimes convenient to use this method to prepare halogenoamminemetal compounds (14). 

Just as water can be expelled from solid aquo complexes, ammonia and amines can sometimes be liberated from metal ammines. This procedure is 

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