Modular inorganic structures

The utility of considering, when applicable, crystal structures as based on complex modules that occur in varied structures, has been demonstrated on describing inorganic materials in several series. In particular, the method has been applied to modelling unknown modular crystal structures. The method is useful when a direct solution of the crystal structure is impracticable, e.g. because suitable single crystals are not available and because information from the powder diffraction pattern is... 

Apart from structures that are built of slabs, modular structures that can be constructed of columns in a jigsawlike assembly are well known. In the complex chemistry of the cuprate superconductors and related inorganic oxides, series of structures that are described as tubular, stairlike, and so on have been characterized. Alloy structures that are built of columns of intersecting structures are also well known. Structures built of linked columns, tunnels, and intersecting slabs are also found in minerals. Only one of these more complex structure types will be described, the niobium oxide block structures, chosen as they played a significant role in the history of nonstoichiometry. 

An integrated, modular system for molecular visualization and computation of organic, inorganic, peptide, and polymeric compounds. Stick, ball-and-stick, and space-filling representations. Chem-X/DRAW for 2D and 3D structure drawing. PCs (under DOS and Windows) and Macintosh. 

In the following sections we provide examples of modelling unknown inorganic modular stmctures and discuss the related series. Further examples are available elsewhere [2] unfortunately, often in the literature the inputs from concepts of modular crystallography are not explicitly quoted. The numbers of modular stmctures are increasing rapidly, also because layered materials are increasingly a matter of intensive research [22]. As stated above, as the description of these structures is typically not given in terms of modularity, they can escape a search on keywords. 

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