Research On Crystal Structure And Its Symmetry By Computer Simulation

The knowledge of crystal structure and its symmetrical operation, the relation between micro structure and macroscopically appearance, growth of the crystal, crystal defect, XRD of crystal structure and typical crystal, is chief part in Crystallography, which is abstract and difficult to understand for students. To facilitate teaching and help students to comprehend, we exploited the computer-assisted instruction software on this knowledge.The teaching software related to seven main parts of crystallchemical knowledge--crystal boundary, crystal symmetry, crystal structure, crystal growth, crystal defect, XRD and typical crystal. Crystal boundary was described from forty-seven single forms and some representative combinative forms of crystal systems. For expatiating crystal symmetry, eight symmetrical elements and its operation which included Rotation, Reflection, Conversion, Rotation and Conversion, Rotation and Reflection, Parallel move, Rotation and Motion, Reflection and Motion was introduced, also was fourteen crystal lattices and thirty-two point groups displayed. There were three parts of bond's kinds, ball's close packing and typical crystal in crystal structure. Among them bond's kinds displayed covalent bond, ionic bond, metallic bond and intermolecular force; ball's close packing introduced closest packing, close-packed and crystal & close-packed; and typical crystal displayed beautiful pictures of crystal minerals which included natural elements, sulfide & its similar compound, oxidate & hydroxide, oxysalt. And some sophisticated theoretical models and some growth habit were introduced in crystal growth. Crystal defect was simulated and illustrated from point defect, line imperfection, face defect and body defect. And in crystal XRD the generation of X-ray and the crystal diffraction effect on X-ray ware introduced.This software combined the multimedia technology and three-dimensional interactive technology, and so it was innovative for software's design, instructional conception and the construction of animation. The function of three-dimensional interactive came true with Cult3d and kinds of media material were interfused by the multimedia assembly tools of Director.All the knowledge above was simulated by computer by means of model's production, animation design and interaction manipulation, so it was very convenient for chemical teaching and for students to learn knowledge of crystal. Other then, students' interest on chemical study could be greatly improved by using the software, because it combined kinds of multimedia representations together.