The Overview pages first illustrate what is and what is not a symmetry operation, and what constitutes a symmetry element versus a symmetry operation. It also illustrates the complete set of symmetry operations for two molecules and gives a brief flow chart illustrating one method of assigning a molecule to a point group.

Figure 1. A screen shot of the first Overview page from An Animated Interactive Overview of Molecular Symmetry.

Subsequent pages include Student Exercises, Extra Problems, Tutorial Exercises, and Animated Vibrational Modes. Molecular animations of symmetry operations illustrate proper rotations, improper rotations, reflections, and an inversion. 3D images of 42 additional molecules are included with interactive tools for student exercises.

The user can manipulate the interactive 3D animations, viewing the molecule from any molecular orientation. Interactive buttons make it easy for users to change their view of a molecule by varying the color scheme, shading, ignoring or restoring hydrogen atoms, illustrating reflection planes or axes, aligning along certain symmetry axes, etc.

International Chemical Identifiers (InChIs) have been included for all molecules in these Web pages to assist searching the Web for these structures. These pages make extensive use of Jmol (1), an open source project ideally suited for the development of teaching materials such as these. The source code for An Animated Interactive Overview of Molecular Symmetry is easily accessible and may be copied and altered to create customized examples and other Web-based animations or illustrations. A description of how these Web pages and animations were produced appears in this issue of this Journal.

Literature Cited

1. Jmol (accessed Sep 2005).