Cadmium chloride lattice

Vapor-phase intercalation has its advantages and disadvantages. One advantage of vapor-phase intercalation is that the host is forced to retain its stoichiometry. In liquid-phase intercalation, the host can release atoms, or more likely, ions, to the liquid to which it is being exposed to. For example, when the layered semiconductor Cd2 2S6 is soaked in an aqueous solution of potassium chloride and ethylenediaminetetraacidic acid (EDTA), cadmium ions leave the lattice, and potassium ions enter the lattice (Clement et al., 1986) ... 

The halides of cadmium demonstrate the effect on structure of the easier polarisation of an anion by a smaller cation. Cdp2 has the cubic fluorite lattice but the chloride, bromide and iodide form hexagonal crystals based on layer lattices (p. 150). The distances between the layers increase from the chloride to the iodide, with a corresponding reduction in lattice energies. 

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