Bih-Yaw Jin
Zeolites are aluminosilicate minerals consisting of periodic
arrangement of TO4 tetrahedral units, where T is an aluminum or
silicon cation and O is an oxygen anion. A vast zeolite frameworks can
be thought to exist of composite building units, such as truncated
octahedra, prisms, etc, which again are made up of vertex-linked
tetrahedra with oxygen anions located at vertices. In previous Bridges
conferences, we have demonstrated that the bead-chain construction set
can be employed to build the sphere packing sculptures of a few
tetravalent frameworks such as diamond and sodalite, which can be
considered as the space filling tessellation of truncated octahedra,
through suitable 3D weaving processes.
Zeolite A, also known as LTA, can be viewed as a space filling
tessellation of cubes, truncated octahedra, and truncated
cuboctahedra, also known as the cantitruncated cubic honeycomb.
Here, a novel 3D weaving method is used to build the sphere
packing models that contains eight unit cells (2x2x2) of Zeolite A
using carefully chosen bead chains with two different lengths.
Each chain comprises a chain of beads held by a pre-stressed
elastic string. Spherical beads in these models represent oxygen
anions; while smaller cations hidden inside the tetrahedra are not
shown.