7 Crystal Structure Analysis Using the " Superposition " - and

This electronic edition may be freely copied and redistributed for educational or research purposes only. It may not be sold for profit nor incorporated in any product sold for profit without the express pernfission of The long term aim of the Commission on Crystallographic Teaching in establishing this pamphlet programme is to produce a large collection of short statements each dealing with a specific topic at a specific level. The emphasis is on a particular teaching approach and there may well, in time, be pamphlets giving alternative teaching approaches to the same topic. It is not the function of the Commission to decide on the 'best' approach but to make all available so that teachers can make their own selection. Similarly, in due course, we hope that the same topics will be covered at more than one level. The initial selection of ten pamphlets published together represents a sample of the various levels and approaches and it is hoped that it will stimulate many more people to contribute to this scheme. It does not take very long to write a short pamphlet, but its value to someone teaching a topic for the first time can be very great. Each pamphlet is prefaced by a statement of aims, level, necessary background, etc. Broad: To illustrate and illuminate the relation between diffraction pattern and crystal structure, and to draw together direct and vector methods. Specific: To provide a method for solving structures when standard methods fail.