Topological density of nets: a direct calculation

The topological density of a three-dimensional net is currently available after determining its entire coordination sequence. This paper shows that its value can be obtained directly from the set of cycles of the quotient graph of the net. A geometrical tool, the cycles figure of the net has been developed for this purpose. Its construction as a convex polyhedron with triangular faces is described as well as its use for topological density calculations. An exact expression is derived for three-dimensional nets and extended to arbitrary n-dimensional nets. Additionally, this paper describes applications to three-dimensional lattices and nets, n-dimensional diamonds and lonsdaleites.