The fluorite or flu net

P igurt 9.37 rhc four- and cigliL-conncL lcd fluoritu (CaFi) or flu ncl is built from perfect tetrahedra and cubes. 

The table on the next page concludes this chapter. 

Net Vertex Symbol Short Symbol Connect Nodes  

Tlie main reasons to develop a mathemaUcal formalism of 3D-nets are  

We will not attempt to make a rigorous derivation of the mathematical concepts and equations used in the description of 3D-nets. A number of texts are already devoted to this [1-3J. What we want to do is to provide a more popular description of the mathematics behind nets and perhaps this will be a useful introduction to such more advanced works for the practicing chemist. For those without these ambitions we will simply try to show some of the beauty and usefulness of this approach. 

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