Demonstration on the use of the interactive exercises in plane group symmetry.

The red circles indicate the positions of left-clicks (Windows) or clicks (Mac).

For rotation axes, simply click on the symbol in the toolbook to the right, then click as many sites as you recognize as having that symmetry -- at least enough to locate all sites in a repeating pattern.

For unit cells, click on the open parallelogram and then click at the four corners of the unt cell.

For asymmetric units, click on the 3, 4 or 5 sided symbol then click at the 3, 4 or 5 corners of the asymmetric unit.

For mirrors and glides, click on the symbol and then click at either end of the line you wish to draw. See demo.