Nets with three- and six-connected nodes

This is a more common class of nets, and it includes a net that may be familiar from your undergraduate studies, the rutile net. 

We will consider one more net of this class since it is important to see how trigonal prismatic nodes can connect to trigonal nodes (the RCSR lists another seven three- and six-connected nets). 

We know of no examples of this net and will therefore move on to the four-and six-connected nets. 

Although rare in the field of molecular based nets, we will also in this class have well known inorganic type structures . We have, moreover, four basic geometries to chose from square planar, tetrahedral, octahedral and trigonal prismatic. We thus in principal need to consider at least four different subclasses of nets in this section. Moreover, as with all nets of this type, there is also the stoichiometry between the nodes to consider. 

However, as the examples are very scarce we will restrict this section to a few selected cases, all based on more or less distorted tetrahedral and octahedral nodes. 

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