Using Visualization Tools to Improve Undergraduates' Understanding of Crystal Structure

In order to understand many of the important ideas in materials science, students need to have some understanding of crystal structure and symmetry. But many undergraduate students find crystal symmetry a difficult and highly abstract subject. One of the reasons for this is the use of difficult 2-D representations of complicated 3-D structures. Although many teachers use physical models to help give their students a sense of the structure, physical models are limited in the information they can provide. Using computers to visualize the crystal structure provides flexibility and the ability to link related concepts like symmetry or close packing. This paper reports on CrystalVis, a new visualization tool for crystal structures that is under development at UC Berkeley. The CrystalVis program displays crystals in a variety of ways allowing the student to rotate and zoom in on the crystal so as to get a better sense of the 3D structure. The program has just begun to be used in classes at UCB both as a lecture aid and for students to get hands on experience with crystal structures. The paper reports on the results from these classes and the plans for use the program in the future.