Many atoms in contact The solid state as a giant molecule

2 Many atoms in contact The solid state as a giant molecule 

2 Bonding aspects From atoms to solid state 

In this case the rock salt structure is realized very early on (N 10). Molecular units can only be compositionally defined but not structurally or energetically identified. The interior of the giant molecule , the bulk, is structurally screened by the siufaces from the ambient. The surface region is, as it were, constituted by the terminal groups of the giant molecule, and is of fundamental importance in particular for the kinetics (see Section 5.4). Phase transformations correspond to rearrangement reactions of the total giant molecule. But let us now address the behaviour of electrons in the solid. 

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