Difference between revisions of "Superstructure"
From Online Dictionary of Crystallography
(Created page with "<font color="blue">Surstructure </font> (''Fr''). <font color="black">Superstruttura </font> (''It''). <font color="purple">超構造 </font> (''Ja''). A '''superstructure''' i...")
Revision as of 08:57, 17 February 2019
Surstructure (Fr). Superstruttura (It). 超構造 (Ja).
A superstructure is a crystal structure S’ obtained from another crystal structure (called a basic structure) S under the following conditions:
- the space group G’ of S is a subgroup of the space group G of S;
- the translation subgroup T(G’) of S’ is a subgroup of translation subgroup T(G) of S, i.e. the unit cell of S’ is a supercell of the unit cell of S and the lattice of S’ is sublattice of the lattice of S;
- the point group of P’ of S’ may either coincide with the point group P of S or be a subgroup of it;
- at least one of the Wyckoff positions of S is split into two or more independent Wyckoff positions of S’ and the corresponding crystallographic orbits are occupied by chemically different atoms.