Why Are Ionic Materials Generally Solids

There are other architectures of sohd ionic compounds, and they all share the above common feature of close packing of oppositely charged ions, in order to optimize the attraction between the cations and the anions. 

FIGURE 8.3 (a) The structure of solid Na+Cr. (b) The stmcture of solid CI2. Note the short distance within each CI2 molecule and the long distances between molecules. (The image presenting the structure of solid CI2 is a public domain image obtained from http //commons.wikimedia.Org/wiki/File Chlorine-unit-cell-3D-balls.png.) 

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