The surface atoms of a crystal may rearrange spontaneously with a different symmetry from that of the bulk structure. This reconstruction process is caused by the surface free energy. An example can be found on silicon surfaces named as Si(111) 7x7. The reconstruction depends on the crystallographic orientation (here denoted as 111 and the symmetry of the superstructure is given by the two following digits). Superlattices are sometimes referred to as superstructures.

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Artificial metallic superlattices are multilayered thin films, prepared by alternately depositing two elements using vacuum deposition or sputtering techniques. A wide spectrum of elements and compounds are suitable for deposition into superlattice structures, and the range of properties displayed by the resulting superstructures is greatly dependent upon the properties of both individual lattices as well as the interaction between them. [see The Superlattice Collection for images.]

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Artificial metallic superlattices are multilayered thin films, prepared by alternately depositing two elements using vacuum deposition or sputtering techniques. A wide spectrum of elements and compounds are suitable for deposition into superlattice structures, and the range of properties displayed by the resulting superstructures is greatly dependent upon the properties of both individual lattices as well as the interaction between them. [see The Superlattice Collection for images.]

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