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JCE WebWare: Web-Based Learning Aids
William F. Coleman Wellesley College Wellesley, MA 02481
Teaching Molecular Symmetry with JCE WebWare Interactive, Web-based teaching tools: that is what JCE WebWare is all about. This month we present two great tools that illustrate and help teach molecular symmetry. They are also examples of two types of Web-based teaching tools you can find at JCE WebWare: digital assets and learning objects. 3D Molecular Symmetry Shockwave is a companion application to 3D Normal Modes Shockwave by the same authors, and published previously in this Journal (1). These applications use the Shockwave Web browser plug-in (2) to provide interactive, Web-based 3D animations of concepts that may be difficult for many students. With 3D Molecular Symmetry Shockwave, instructors and students can choose a molecule, orient it appropriately on the screen, choose any of its symmetry elements, and animate the corresponding symmetry operation in three dimensions. An Animated Interactive Overview of Molecular Symmetry uses Jmol, a Java-based browser applet (3), in an interactive tutorial for teaching molecular symmetry. Students learn molecular symmetry by working through a series of instructional Web pages illustrated and enhanced with interactive Jmol structures. 3D Molecular Symmetry Shockwave is an example of a digital asset: a document, image, video, animation, etc. that can be used—and reused—in many different settings. For example, by including appropriate facts, concepts, principles, etc., you could use this animation in lecture as a demonstration, to enhance a seminar presentation, or as part of a student tutorial exercise or homework assignment. There are many such digital assets available in JCE WebWare; just add your own context to use it your way! By contrast, An Animated Interactive Overview of Molecular Symmetry is an example of a learning object: a selfcontained lesson, with a single learning objective. Learning objects include both digital assets (in this case the Jmol animations) along with facts, concepts, principles, etc. to form complete, self-contained learning units: the digital equivalent perhaps to a chapter subtopic in a textbook. Although they are ready to use as is, you can still modify learning objects as you need. You can explore these and other digital assets and learning objects in the peer-reviewed and open review collections of JCE WebWare at http://www.JCE.DivCHED.org/JCEDLib/ WebWare/. We invite you to submit digital assets and learning objects that you have created for use in your classroom to JCE WebWare, either for our open review collection or to be peer reviewed for formal publication.
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Edward W. Fedosky University of Wisconsin–Madison Madison, WI 53715
3D Molecular Symmetry Shockwave: A Web Application for Interactive Visualization and Three-Dimensional Perception of Molecular Symmetry by Nickolas D. Charistos, Constantinos A. Tsipis, and Michael P. Sigalas, Aristotle University of Thessaloniki, Department of Chemistry, Laboratory of Applied Quantum Chemistry, 54124 Thessaloniki, Greece Keywords: Chemoinformatics; Physical Chemistry; First-Year Undergraduate / General; Second-Year Undergraduate; Upper-Division Undergraduate; Computer-Based Learning; Internet / Web-Based Learning; Group Theory / Symmetry; Molecular Modeling; Molecular Properties / Structure Requires: Web browser with Macromedia Shockwave plug-in installed
One of the ongoing challenges in teaching chemistry is helping students explore various structural features of molecules. It can be difficult for students to visualize the three-dimensional shape of a molecule from a two-dimensional printed image. Using a molecular modelling kit in the classroom helps, but such models can be difficult for students to see when demonstrated by an instructor. These difficulties are more pronounced in teaching symmetry, especially recognition of various symmetry elements within a molecule and conceptualization of the symmetry operations. 3D Molecular Symmetry Shockwave is a Web-based application for interactive visualization and three-dimensional perception of molecular symmetry. The user interface is simple, and students learn how to use the program from the built-in help screens. The animation uses the Macromedia Shockwave browser plug-in, and requires a download of only 256 KB, allowing it to be used even with low bandwidth Internet connections. Its performance is comparable to a desktop application. With 3D Molecular Symmetry Shockwave students and instructors can: • Display molecules in ball-and-stick or wireframe representation • Display each symmetry element of a molecule in a 3D environment and animate the corresponding symmetry operation • Rotate, translate, or zoom a molecule to any viewpoint
JCE WebWare—a dynamic feature column http://www.jce.divched.org/JCEDLib/WebWare/
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Vol. 82 No. 11 November 2005
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Journal of Chemical Education
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Figure 1. The main screen from Symmetry Elements mode of 3D Molecular Symmetry Shockwave.
Figure 2. The main screen from Point Groups mode of 3D Molecular Symmetry Shockwave.
• Store and recall preferred viewpoints of the molecule for later use
Symmetry Elements and Operations and Symmetry and Point Groups are similar programs for Mac OS and Windows respectively, previously published by JCE Software (6, 7). However, they have limited capabilities of manipulating a molecule and its symmetry elements in a 3D environment. Also, they do not have a database of molecules that can be searched according to specific symmetry criteria. On the other hand, Symmetry and Point Groups does lead students through a flow chart of questions to help them identify the point group of a molecule, a feature that is not available in 3D Molecular Symmetry Shockwave.
• View information about the selected molecule, its symmetry elements and its point group
3D Molecular Symmetry Shockwave also serves as a searchable database of structural and symmetry data for 47 organic and inorganic molecules, including all symmetry point groups of chemical interest. This database can be accessed in two modes. In the Symmetry Elements mode the user can search the database to find all molecules having symmetry elements of a certain type (for example Cn) or a particular symmetry element (v). In the Point Groups mode the user can search the database to find all molecules having a point group of a certain type (Cnh) or a particular point group (D2d). The main screen from Symmetry Elements mode is shown in Figure 1. A user has searched the database to find all molecules having C3 rotation axes. She has selected cubane from the results, and one of its six C3 rotation axes, and is ready to start the animation of this symmetry operation. The main screen from Point Groups mode is shown in Figure 2. A user has searched the database to find all molecules having point groups of Dnd type. He has selected ferrocene from the list of molecules, and one of its two C5 rotation axes, and is ready to start the animation. 3D Molecular Symmetry Shockwave is suitable for undergraduate students in chemistry, and can be used with typical textbooks (4, 5) as a self-paced learning tool, as well as a presentation tool.
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Journal of Chemical Education
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Literature Cited 1. Charistos, N. D.; Tsipis, C. A.; Sigalas, M. P. J. Chem. Educ. 2004, 81, 1231–1232. 2. The Shockwave Player may be downloaded at http:// www.macromedia.com/shockwave/download/ (accessed Sep 2005) 3. Jmol may be downloaded at http://jmol.sourceforge.net (accessed Sep 2005). 4. Douglas, B. E.; Holingsworth, C. A. Symmetry in Bonding and Spectra, An Introduction; Academic Press: New York, 1985. 5. Cotton, F. A. Chemical Applications of Group Theory, 2nd ed.; John Wiley & Sons: New York, 1971. 6. Vining, William J.; Grosso, Robert P., Jr. J. Chem. Educ. 2003, 80, 110. 7. Lee, A. W. M.; Leung, K. M.; Kwong, D. W. J.; Chan, C. L. J. Chem. Educ. Software 8C2.
Vol. 82 No. 11 November 2005
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