Homeotect structure types

A few important examples of groups of homeotect structure types will be described in the following sections. A short list follows, in which the Jagodzinski-Wyckoff notation of the stacking pattern has been inserted according to the previously given indications. 

Close-packed element structure types. The structures of the close-packed metals are a simple well-known example of homeotect structure types. We have seen that the following metals can be considered as reference types. 

The Laves phases form a homeotect structure type set (a family of polytypic structures). In all of them, described in terms of a hexagonal cell, three closely spaced 36 nets of atoms are followed (in the z direction of the same cell) by a 3636 net. The 36 nets are stacked on the same site as the kagome 3636 nets which they surround. For instance (3-BAC- -CAB in the two slabs MgZn2-type (h) structure, (3-BAC- -CBA-a-ACB in the three slabs MgCu2-type (c) structure,... 

A few general remarks about homeotect structures. Other important sets of homeotect structure types are those related to disilicide structure types (MoSi2, CrSi2, etc.), cadmium halide structure types, etc. (See Parthe 1964, Hyde and Anderson 1989), or presented by certain groups of compounds such as rare earth trialuminides (Van Vucht and Buschow 1965). 

The sphalerite- and wurtzite-type structures belong to a homeotect structure type set. The layer stacking sequence symbols (triangular nets) of the two structures are ... 

In the p vs. e diagram every structure type is generally characterized by its own individually shaped space-filling curve. The space-filling curves, however, of all binary structures belonging to one homeotect structure set coincide with one curve (see 3.9.2). 

The La- and Sm-type structures belong to the same homeotect type set as Mg and Cu. All these close-packed element structures are stacking variants of identical slab types (monatomic triangular nets). 

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