26 Jan 2018

# Symmetry Challenge -- 2018!

Submitted by Adam R. Johnson, Harvey Mudd College

Well, it's that time again... time to announce the annual VIPEr symmetry challenge. First offered in 2009, it had several years of hibernation before coming back in 2017. If you're looking for a fun competition to pit your students against students across the world, here it is. Last year's results were also posted here. Since symmetry is usually an early component of an inorganic course, I'm making the deadline Friday, March 2nd.

Here is text you can hand out in your class:

Here is a chance to show your symmetry skills to all the inorganic chemists and students of inorganic chemistry on www.ionicviper.org!

Given a cube and 6 lines, one (and only one!) on each face of the cube, how many objects of different point group symmetry can you construct?  Each of the six lines must fit edge to edge, vertex to vertex, or edge to vertex on one of each of the 6 faces of the cube.

The student who comes up with the most examples of different point groups (you only get credit for one object from each point group) wins!  Send Professor Adam Johnson an email with your submission. The subject line should say "VIPEr symmetry challenge." For the 2018 contest, submissions are due March 2nd. No submissions received after 5:00 pm Pacific Time on March 2nd will be accepted. The prize will a selection of (yet to be determined) fun VIPEr products including your own snake mascot, and the opportunity to be prominently featured on the VIPEr home page!

Here are two to get you started:
a)  the 6 lines go vertex to vertex, one on each face of the cube. It is a tetrahedron inscribed in a cube with Td symmetry

b)  In this example, the lines are a mixture of edge to edge and vertex to vertex, this object has Cs symmetry.

How many more can you come up with?