W0063

Crystallographic CourseWare: Coordinates and Thermal Parameters. Margaret E. Kastner, Jonathan Greives and Keith DiMarco, Department of Chemistry, Bucknell University, Lewisburg, PA 17837

Crystallographic CourseWare is a growing set of programs designed to assist students in learning crystallography. The assumed audience is upper level undergraduate or beginning graduate students of chemistry. The primary goal is to better enable these students to read papers that contain crystallographic structural information. First written in 1991 for the Macintosh, the original programs have now been converted to a Windows format using ToolBook and MacroMedia Director. These programs discuss crystal growth, unit cells and asymmetric units, 2 and 3 dimensional symmetry elements, plane groups and space groups, and an introduction to reading the International Tables of Crystallography, Volume A. Related units on point group symmetry , exercises in identification of all symmetry elements and exercises in the assignment the Schoenflies symbols have now been added. The new units for presentation here are very simple in concept -- to help students understand how the tables of numbers headed by x, y, z and U₁₁, U₂₂ etc. correspond to thermal ellipsoid plots and packing diagrams.