This is a bag of 100 Tetrahedral metal clusters. This cluster allows for tetravalent coordination compounds as well as sp3 hybridized Carbon for Organic Chemistry because of Carbon's ability to make four bonds. Stereoisomers (R/S), structural and geometric isomers all use these extensively. They are nickel plated.
Posted by Trevor on 20th Feb 2015
In soap bubbles and polycrystals, the grain edges must meet at the tetrahedral angle, which these clusters enforce perfectly. Very good physical models of grains can be built using flexible tubing, which establishes force balance and shows the residual curvature in the edges and faces. The product is useful for constructing all kinds of physical models, higly recommended!
Posted by Michelle Francl on 15th Nov 2014
I buy these in bulk, along with other centers and the tubing. Cut the tubing into thirds and then I have small models I can use with students in office hours, inexpensive enough to let them take them away. When we start VSEPR theory I give everyone a tetrahedral center, a TBP and an octahedral center, along with 4 pieces of tubing of various color (to cut up into 12 "atoms" they can use) and while I lecture on the material, everyone is asked to build their own models.
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