In an inorganic metal salt that contains water molecules, are the water molecules likely to coordinate to the metal centre?

1 Answer
Jul 14, 2017

Well, yes.........


Suppose you dry an hydrate, i.e. #[M{(OH)_2}_6]Cl_3#. As written, the metal is coordinated to 6 aqua ligands. As you dry the salt, water ligands are removed, and a chloride ligand could replace water in the primary coordination sphere of the metal centre.

When you dry transition metals sometimes you heat them to reflux in thionyl choride, or trimethylsilyl chloride; and sometimes you see the slurry of metal salt change colour several times as the last traces of water from the metal. We know that nickel chloride hexahydrate is a green salt, whereas the anhydrous salt is yellow to brown........